Keto Prosciutto Onion Tomato Pizza
Published June 20, 2019 • Updated March 3, 2026
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Salty prosciutto, spicy red onion, and blistered cherry tomatoes on a fathead crust that holds its own. I make this low-carb pizza most Fridays and my kids request it by name.
I put prosciutto on this pizza for one reason: it crisps up in the oven in a way that regular deli meat never will. The thin slices render and curl at the edges while the red onion softens underneath, and the cherry tomatoes blister just enough to give you little pockets of juice across the whole thing. This is my go-to keto pizza when I want something that feels like a real Friday night dinner.
The base is a fathead dough that I’ve been making for years. If you’ve tried my grilled pizza or my crustless pizza, you know I’m not short on pizza options around here. But this one earns its spot because the crust actually holds up under heavy toppings. I load mine with prosciutto, a full cup of mozzarella, red onion, halved cherry tomatoes, and chives, and the center doesn’t buckle.
A few things I’ve learned making this. Let the melted mozzarella cool for a minute before adding the egg. If the cheese is too hot, the egg starts to cook and you get scrambled bits in your dough. An electric mixer or food processor saves you ten minutes of sticky hand-kneading (I use the mixer and yes, dough flies everywhere). Roll the dough between two sheets of parchment to about 1/4 inch thickness. Thinner than that and the crust gets cracker-crispy, which some people want, but I like a little chew.
One of my readers, Joanna, made two of these on a Sunday and ate them through the week. She said the prosciutto held up surprisingly well even on day three. I tested this myself and she’s right. If you want to bring back that fresh-from-the-oven crispiness, put a slice under the broiler for 2-3 minutes. That trick came from a real exchange in the comments and it works every time.
This low carb pizza reheats better than most because the fathead crust doesn’t go soggy the way regular dough does. I usually make it alongside something lighter like my chicken pesto pizza so we have two options for the week. For something completely different, my pizza chicken gives you all the flavors without the crust at all.
The topping combination is what makes this one work. Salty prosciutto, sharp red onion, sweet blistered tomatoes. They balance each other out without any one flavor taking over. Straight out of the oven, this is one of those pizzas that doesn’t need to apologize for anything.
Ingredients
3.5 cups shredded mozzarella cheese, plus 1 cup for toppings -
1.5 cups almond flour
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1 egg
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1 teaspoon baking powder
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1 teaspoon xanthan gum
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½ teaspoon salt
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2 tablespoons pizza sauce
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3 oz prosciutto
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2 tablespoons diced red onion
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4 cherry tomatoes, halved
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2 chives, minced (optional)
Step by Step Instructions
Step by Step Instructions
Preheat oven
Preheat oven to 400 degrees.
Melt cheese
Place 3.5 cups of mozzarella in a microwave-safe glass bowl. Microwave for about two minutes until cheese is melted. Stir to combine and make sure all of the cheese is melted. Remove from microwave and let the mixture cool.
Mix dry ingredients
In a large separate bowl, mix together the almond flour, baking powder, xanthan gum, and salt. Set aside.
Mix egg and cheese
Add in your egg to the melted mozzarella cheese. Mix using an electric mixer until combined.
Make dough
Slowly add the almond flour mixture to the cheese mixture. Using an electric mixer or food processor, stir until you have a uniform dough. Don’t be surprised if dough goes flying if you are using the mixer! This can happen, but this is an easy way to combine the mixtures in order to make the best fat head dough. If you don’t have an electric mixer or food processor, I recommend kneading the dough by hand until it comes together. This is a messy and time-consuming process, but the end result is the same – fat head pizza.
Knead pizza dough
Once combined, form a big dough ball. Knead the dough a couple of times on a lightly almond floured surface to ensure the dough is uniform in appearance and all ingredients are fully combined.
Layer between parchment
Place the ball in between two pieces of parchment paper.
Roll out crust
Roll out dough to desired thickness. Remove top parchment layer and place on top of a baking sheet.
Saucy
Spread pizza sauce evenly over the pizza crust.
Toppings
Sprinkle 1 cup of mozzarella cheese all over the crust. Add prosciutto. Sprinkle diced red onion evenly over the pizza. Add cherry tomatoes all over the pizza dough. Sprinkle chives if using.
Bake
Bake at 400 degrees for 10 – 12 minutes or until cheese is starting to brown and is bubbly.
Nutrition disclaimer
The nutrition information provided is an estimate and is for informational purposes only. I am a Doctor of Pharmacy (Pharm.D.); however, this content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified health provider before making any lifestyle changes or beginning a new nutrition program.
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Get My Macros + Recipes →Frequently Asked Questions
Can I use deli turkey instead of prosciutto?
I tested this after a reader asked (her husband doesn't eat pork). Deli turkey works fine as a topping swap. The only difference is texture: prosciutto renders in the oven and gets crispy at the edges, while turkey stays soft. The fat from the prosciutto doesn't touch the crust, so the base comes out exactly the same either way. If you want to try a completely different topping combination, my BBQ pulled pork pizza is another favorite.
Does prosciutto need to be cooked before going on the pizza?
No, and I actually prefer it raw going in. I lay the prosciutto slices directly on top of the cheese before baking. The oven does all the work at 400 degrees, and the slices crisp up and curl at the edges as the pizza bakes. If you pre-cook the prosciutto, it tends to dry out too much by the time the pizza is done.
How do I reheat leftover slices without making them soggy?
I've tried the microwave and the oven, and there's really only one answer: 2-3 minutes under the broiler. The broiler brings back the crispiness on the prosciutto and re-melts the cheese without making the fathead crust rubbery. I discovered this from a conversation in the comments and now it's the only way I reheat this pizza.
Can I pre-bake the crust ahead of time and add toppings later?
I've done this and it works well for meal prep. Bake the crust alone at 400 degrees for about 8 minutes until it's set and lightly golden. Let it cool, then wrap it in plastic and refrigerate for up to 3 days. When you're ready, add your toppings and bake for another 8-10 minutes. The crust is actually a little crispier this way because it gets two rounds in the oven.
What can I substitute for almond flour if I have a nut allergy?
I've tested sunflower seed flour as a swap and it does work. The texture is close to almond flour, though the flavor is a little earthier. One thing that catches people off guard: the crust will turn slightly green from a reaction between the sunflower seeds and the baking powder. Completely normal, completely safe, just unexpected the first time.
Can I use a different cheese instead of mozzarella for the crust?
I've tried provolone and gouda in this crust, and they both melt fine. But mozzarella gives you the best stretch, which is what holds the dough together when you roll it out. If you swap cheeses, the dough can be a bit more crumbly and harder to work with. My recommendation is to stick with mozzarella for the crust and save the flavor experiments for the toppings. If you want a completely different crust approach, my chicken crust pizza skips the dairy in the base entirely.
Can I freeze the fathead crust?
I freeze these regularly. Bake the crust without toppings first, let it cool completely, then wrap tightly in plastic wrap and foil. It keeps for about 2 months in the freezer. When you're ready, I go straight from frozen to oven: add toppings and bake at 400 degrees for 12-15 minutes. The texture holds up well, though it won't be quite as chewy as fresh.
Can I grill this instead of baking it?
I have a whole grilled pizza recipe if you want the full rundown, but the short answer is yes. The trick is grilling the crust on one side first, then flipping it, adding toppings, and closing the lid to melt the cheese. I use medium-high heat and keep a close eye on it because fathead dough can go from golden to burnt fast. The smoky char you get from the grill is worth the extra attention.
My son ate all the prosciutto off his slice first, then asked for another piece and did the exact same thing. Review complete.
Made a double batch on Sunday and the fathead crust was still holding its crunch on Thursday, so this is officially my Friday meal prep standard.
Sunday to Thursday crunch is the goal. That crust doesn't quit.
My husband never comments on dinner, but mid-slice he asked what was on it. The prosciutto and blistered tomatoes got him.
Made this last Friday and it was so good (my husband ate three pieces which never happens with keto food) but the center stayed pretty soft even after 30 minutes at 400. I used parchment paper on a regular baking sheet. Is that what's causing it, or do I need to prebake the crust before adding the toppings?
Parchment on a regular baking sheet is probably it. Dark pan or cast iron gets way hotter underneath and crisps the bottom up faster. You can also pre-bake the crust 8 minutes before adding toppings, that combo usually fixes the soft center.
First time making fathead dough and I genuinely wasn't sure the xanthan gum step was going to work. It did. Prosciutto crisped at the edges in a way that made the whole thing. Does the crust hold up if you reheat in an oven the next day?
Broiler, not oven. 2-3 minutes and the prosciutto crisps right up.
Made this five or six times now, and somewhere around batch three I started pre-baking the crust for about five minutes before adding anything. The mozzarella sets up firmer that way and the toppings don't steam the surface. The prosciutto still crisps at the edges, the cherry tomatoes blister just right, and I actually get that crackle in the crust I was chasing from the start. This is the Friday pizza in my house now.
Five minutes is the sweet spot for same-day. I go 8 when I'm meal prepping and the crust needs to hold overnight in the fridge, but right before topping works. The crackle you're describing is the whole reason fathead crust is worth making and most people never get there.
One thing I figured out after the second batch: pat the cherry tomatoes dry. First time I didn't and there was a little moisture pooling under them mid-bake, not enough to ruin anything but you can tell. The prosciutto I now add in the last three or four minutes (started doing that after the first attempt came out a bit chewy from the full bake time), and that fixed it. The xanthan gum is doing real work in this dough, holds together noticeably better than other fathead recipes that skip it, so don't swap it out. Crust needs the full time at 400 for the edges to get properly golden. Check around 15 minutes since ovens vary. Two batches to dial in but writing this down in case it saves someone the trial run.
The tomato tip is real. I skipped the pat once and saw the same thing, little moisture ring forming under them by the halfway point. Doesn't wreck it but you notice. Good call adding it in late too, that chewy prosciutto thing is fixable exactly the way you did it.
There was a place in our old neighborhood that made a prosciutto and tomato pizza I thought I'd never eat again once I went keto. The blistered cherry tomatoes here brought that back, and the fathead crust held up in a way I wasn't expecting. Genuinely grateful this exists.
Those neighborhood spots stick with you. The blistered tomatoes took me the longest to nail on this one. Glad it landed right.
Caramelized the red onion first, maybe 10 minutes, and that sweetness against the prosciutto completely changed it. Next time I'll add more sauce on the base but this combo is really working.
Ten minutes gets them actually sweet. That against the prosciutto salt is its own thing. Two tablespoons barely covers the crust anyway, so more sauce makes sense.
Made this for a dinner party last weekend and honestly wasn't expecting much. The prosciutto and blistered cherry tomatoes made it look like something from a wine bar, which helped. Two friends who couldn't care less about low-carb had two slices each before I mentioned it was keto. When I did, one of them got up to actually check the crust. She was convinced it was thin regular dough. The xanthan gum is doing something real here; the texture is chewy in a way I haven't gotten from other almond flour doughs. I've been meaning to write this up since the first time a few months ago. Already making it again for Easter.
The crust check. That's always the moment. Xanthan gum is doing that - I tested the same dough without it once and the texture went completely flat, more crumbly than chewy. One teaspoon is holding the whole thing together.
There was this little spot near where I grew up that did a prosciutto and tomato pizza that I stopped letting myself think about when I went keto. The blistered cherry tomatoes on top of this hit me the same way, that slight sweetness from the heat combined with the salt from the prosciutto. I made it on a Tuesday night expecting it to be 'good for keto' and ended up just sitting there finishing a slice slowly. The fathead crust held together better than I expected. I've made a lot of keto pizza over the past two years and most of it reminds me of what I'm missing. This one just reminded me of pizza.
Cut side down at 400 and they blister fast, that sweetness comes out right against all the prosciutto salt. 'Just reminded me of pizza' is the best thing I could read.
I almost skipped this because I've tried two other keto pizza crusts this year and they were both kind of gummy and discouraging (I tossed one of them). The fathead dough here came together faster than anything I'd made before and was easy to handle, which surprised me because I'm not a confident baker. The prosciutto crisps up at the edges where the oven heat hits it, and the cherry tomatoes blister and pool into the sauce underneath. Didn't expect that. I finished my slice before I even realized I was done, and with the other keto crusts I was always very aware I was eating a substitute. Making this again Friday, just because I want to.
That's the fathead. When it's done right you don't notice it's a substitution. Just pizza. Friday's a good call.
Made a double batch on Sunday and kept the crusts par-baked without toppings in the fridge. Added the prosciutto and cherry tomatoes fresh before a quick 375 blast each day. The fathead base holds up better than any other pizza crust I've tried for this, no sogginess even on day three. About 8 minutes from par-baked to done, which is actually realistic on a weeknight.
375 is better for the reheat when you're adding prosciutto fresh. At 400 it can overcrisp before the crust even heats through. Eight minutes really does work.
My husband doesn't eat pork, so no prosciutto. Will thin-sliced deli turkey work, or does the prosciutto fat actually affect how the crust comes out?
Turkey will work. Prosciutto is just a topping here, so the fat doesn't touch the crust. Only thing you lose is the crispiness - prosciutto renders in the oven, turkey stays soft.
I made two of these on Sunday to get through the week, and the prosciutto held up surprisingly well even on day three. Not quite as crispy as fresh out of the oven, but still really good for a Monday night when I have nothing left in me.
Day three prosciutto is honestly better than I expected too. If you want to get some crisp back, 2-3 minutes under the broiler does it.