Almost every week from October through February, this warm, spiced keto pumpkin mug cake gets me through — 5.3g net carbs and 10.6g protein. Ready in about 70 seconds, one serving, nothing left over.
I've been making this since 2018, and it's what I reach for when I want something warm and pumpkin-spiced without pulling out a mixing bowl or turning on the oven. One mug, a handful of ingredients, about 70 seconds in the microwave.
The first time I made a keto pumpkin mug cake, I overcooked it by a solid 15 seconds and ended up with a rubbery puck. That taught me that your microwave wattage is the single biggest variable. Mine is 1000W, and 65 seconds is my exact sweet spot. If yours runs closer to 700W, you'll need 80-90 seconds. The cake should rise and feel set when you give the mug a gentle shake, but still look slightly moist on top. If it jiggles, give it another 10 seconds.
Mug shape matters more than you'd think. A wide, short ramekin cooks more evenly than a tall coffee mug. One of my readers, Allison, found her tall mug needed 85-90 seconds to cook through compared to the standard 65-70 in a ramekin. If you're using a tall mug, just add 15-20 seconds and check.
I keep a jar of pre-mixed dry ingredients on my counter: almond flour, coconut flour, monk fruit, baking powder, pumpkin pie spice, salt. I mix up four or five batches at a time, and the dry mix lasts for weeks in the pantry. When I want one, I scoop out the dry portion, crack an egg, add melted butter, pumpkin puree, and vanilla. Two minutes from craving to eating. Another reader, Debi, does the same thing with individual baggies, which is even faster.
One tip from my reader Brian that I now swear by: double the pumpkin pie spice. The original half teaspoon is restrained. A full teaspoon makes the warm spice flavor come through the way it should. I've been making it that way since he mentioned it.
This is a low carb single-serve dessert, so there's nothing left over to tempt you the next day. If you're new to keto baking, this is a forgiving place to start. Almond flour and coconut flour together give it structure without any grittiness, and the egg does the heavy lifting for rise.
I top it with fresh whipped cream, and at Thanksgiving I make just this one serving while everyone else has pie.
Do You Need to Grease the Mug?
You don’t have to grease the mug. If you want to flip the cake out, spray it with cooking spray before adding the batter. I use avocado or coconut cooking spray.
In a mug or ramekin, combine all of the mug cake ingredients.
2
Mix it
Mix until combined.
3
Microwave it
Microwave for 60 to 75 seconds or until the cake has risen and is set in the middle. It should not be wobbly when you shake it.
4
Let cool
Remove from microwave to let cool.
Nutrition
Per serving: 1 mug cake
Calories
394
Fat
34.9g
Protein
10.6g
Total carbs
10.4g
Net carbs
5.3g
Nutrition is an estimate calculated from the ingredients listed. Brands vary, so check labels if you track closely.
Frequently Asked Questions
How long do I microwave this?
I've tested this in my 1000W microwave dozens of times, and 65 seconds is my sweet spot. If yours is lower wattage (around 700W), you'll need closer to 80-90 seconds. The general starting point most of my readers land on is 70 seconds. Give the mug a gentle shake when the time is up. If the center jiggles, add 10 seconds. If it's firm and slightly moist on top, it's done.
Why did my cake turn out dense or rubbery?
Two things cause this, and I've hit both. Overcooking makes it rubbery. Even 10-15 extra seconds can do it. Dense usually means you let it sit too long after cooking. My reader Rosa nailed this: the egg keeps setting from residual heat even after you pull it out. Eat it within a couple minutes of cooking for the best texture. Shave 5 seconds off your cook time and see if that helps.
Can I make this in the oven instead of the microwave?
I've done it in a ramekin at 350F for about 12-15 minutes. The texture comes out a little more cake-like compared to the microwave version, which I actually prefer sometimes. Just watch it closely after 12 minutes. You want it set on top but not dried out.
Can I make a batch of the dry mix ahead of time?
This is how I do it now. I mix up four or five batches of the dry ingredients and keep them in a jar on my counter. The mix lasts for weeks. When I want one, I scoop out a portion, add egg, melted butter, pumpkin puree, and vanilla. Two minutes from craving to eating. I do the same thing for my chocolate chip version.
What is the difference between pumpkin puree and pumpkin pie filling?
I use pure pumpkin puree, not pie filling. Pie filling has added sugar and spices, which wrecks the carb count and throws off the sweetness. I usually grab Libby's 100% pure pumpkin. If the can says 'pie filling' or 'pie mix' anywhere on the label, put it back.
Can I use a tall mug or does it have to be a ramekin?
Both work, but cook time changes. I prefer a wide ramekin because it cooks more evenly. My reader Allison used a tall coffee mug and found she needed 85-90 seconds instead of the usual 65-70. If you're using a tall mug, add 15-20 extra seconds and check the center before you eat it.
Can I make this dairy-free?
I've made it with coconut oil instead of butter and it works well. The coconut flavor is subtle and doesn't overpower the pumpkin at all. Use the same amount, just make sure it's melted. My keto cinnamon coffee cake uses the same low carb swap if you want another dairy-free option.
What can I substitute for monk fruit sweetener?
I've used erythritol and it works fine. Stevia works too, but I start with less because it's more concentrated. My go-to is monk fruit because I like how it tastes, but sweetness varies between brands so I always taste the batter before I microwave it. You can add more, but you can't take it out.
The edges pull from the mug walls right at 70 seconds, that’s my done signal now. Two tablespoons of puree is subtle. Really subtle. The spice blend carries most of the flavor, which is fine, but if you want actual pumpkin flavor bump it to three tablespoons. The coconut flour handles the extra moisture no problem. The almond/coconut split keeps the center from going dense and wet; the coconut pulls moisture from the egg and firms it up. Four stars. Pumpkin flavor was quieter than I was expecting.
Swap the vanilla for maple extract, just do it, I know it sounds like it’ll make the whole thing taste like a pancake but the pumpkin just comes forward more instead and it honestly tastes like something I’d pay for. Had no vanilla one night and a random bottle left over from some holiday baking thing I’d forgotten about, and now that’s the only way I make this.
Out of coconut flour right now, if I just bump the almond flour to 3 tablespoons total does it still set up in 70 seconds or does this actually need both flours to get the right texture?
Hi Amanda, that single tablespoon of coconut flour soaks up more liquid than you’d guess, so 3 tablespoons of almond flour won’t set the same way at 70 seconds. I’d go 4 or 5 tablespoons instead and add another 10 to 15 seconds. It’ll still be a little softer in the middle.
Pressed the center to check if it was set and got this springy give I wasn’t expecting. I’m new to keto, first attempt, went in ready to throw the whole thing out. The coconut flour and almond flour together do something I still can’t explain, but it works. One thing though – eat it immediately. Mine cooled fast and lost whatever made it good. Anyone know if you can make two at once, or does the microwave time change completely?
Hi Denise, I run them one at a time. Two mugs in there together cook unevenly and the time jumps up closer to two minutes, so the first one sits there cooling while the second finishes. Back to back at 60 to 75 seconds each is faster than it sounds.
Made this twice now, once last fall and again this weekend since the last thing I wanted was the oven running on a 95-degree day. The timing is where I keep second-guessing myself. My microwave is 1100 watts, and both times I pulled it at 70 seconds but the center still looked a little underdone, even though it set up fine after cooling. I wasn’t sure if that soft center right at the end of cooking is expected, or if I should be pushing it closer to 90 seconds. Is there a visual cue to watch for, beyond ‘risen and set in the middle,’ since that’s genuinely hard to judge through a ceramic mug? I want to stop overcooking the edges trying to make the top look done.
I’ve had the same thing happen at home. Half a teaspoon of pumpkin pie spice in a warm mug does not stay quiet. Hope your coworker got the recipe, Andre.
There was a little bakery near my first apartment that sold individual pumpkin squares in the fall, wrapped in wax paper. This hits that exact same note. Grateful for the 70-second version.
Just made this for the first time and went in with pretty low expectations. It’s been too hot to turn on the oven and a 70-second microwave cake seemed almost suspiciously convenient. But the pumpkin pie spice smell that came out was genuinely cozy, which felt strange in the middle of June heat. Mine came out a little dense in the center (I think I overmixed), but the flavor was really good for something that took less than two minutes. Stirring less next time.
Stirring less will fix it. But eat it the second it comes out too. The egg keeps setting after the microwave stops, and even a minute makes the center noticeably denser.
My son walked in while this was in the microwave and goes ‘why does it smell like fall?’ (it is March) and then ate my mug cake before I even got to it. Made a second one immediately. Something about pumpkin pie spice hitting in 70 seconds just works. Did not see that coming from a mug cake.
Eight times since October is solid. The density when it sits – that’s residual heat, the egg keeps setting after you pull it out. Shave 5 seconds off and eat it fast.
Tried doubling the pumpkin pie spice and wow, it hits completely different. Also figured out 70 seconds is the sweet spot in my microwave, 60 left the center still wobbly. Worth the extra 10 seconds every time.
70 seconds is smart, microwave wattage varies so much. The spice thing tracks too, the original amount is pretty restrained. Mine is a 1000W and 65 seconds is my spot.
Loved the flavors and the ease of mixing up. I made in a tall mug and had to increase the cook time to 85-90 seconds. Great for the fall pumpkin cravings!
This makes an amazing pumpkin dessert cake😋 And it’s so easy. I make up a few baggies of the dry ingredients so that it’s half ready. Perfect ANYTIME 👍
This morning I found this recipe and decided to try it. I opened a can of pumpkin for another recipe the day before, only used 1/4 cup of so I wanted to use the leftovers. As I made this recipe, I mixed the ingredients in a bowl and then poured it in a big coffee mug as my ramekins that I have are too small. It took 2 minutes to fully cook this mug cake in microwave. I let it sit for a few minutes and then turned it upside down onto a plate. It was perfectly cooked. I cut it in half and it was a perfect serving size. So bonus that one recipe will make us two servings. I loved how it is very moist and so tasty!!!! I added whipped cream and I really enjoyed this dessert. Thank you I will be making this again for sure!
Two minutes sounds right for a coffee mug. I do 65-70 in a wide ramekin, but taller takes longer to cook through. Cutting it in half for two servings, I might steal that.
This recipe has gotten me through the doldrums of my restrictive Keto diet. It’s easy to make, delicious AND you only have 1 serving so there is no next day pressure to eat more. I have already made this 4 times since December and will continue to make it as long as there is pumpkin in my pantry.
Four times since December is basically a weekly habit at this point. The one-serving thing is real, it’s why I keep coming back to mug cakes. Nothing to negotiate with yourself about later.
Was craving a pumpkin mugcake and came across this recipe. It was perfect! Makes a very generously-sized mug cake full of pumpkin flavor. Definitely making this again. Thank you for such a quick, easy and tasty recipe.
