Buttery cinnamon pecans crown this keto sweet potato casserole that tastes just like the holiday classic, only 2.2g net carbs. Pumpkin and cauliflower stand in for the starchy originals, and I honestly think it tastes even better.
My Thanksgiving table has to include the classics: mashed cauliflower, green bean casserole, and keto stuffing, because it just wouldn’t feel like the holiday without them. I spent years trying to recreate the casserole my family has made every November since I was a kid. The traditional version was off limits, and every low-carb substitute I tried fell flat. Then I found the answer, and it was two vegetables that don’t seem to belong together: pumpkin and cauliflower.
Pumpkin brings that natural sweetness and silky texture, while cauliflower tones it down with a mild, earthy flavor that keeps everything from tasting overly sweet. When you blend them together with cream cheese, eggs, butter, cinnamon, and nutmeg, you get a creamy, rich filling that’s shockingly close to the original. It fooled my husband, and he’s not easy to fool when it comes to Thanksgiving classics.
The real secret is how I handle the cauliflower. I cook frozen cauliflower rice in a completely dry skillet for 7-10 minutes until every bit of moisture evaporates. That step eliminates the cauliflower smell and flavor entirely. Once it’s dry and fluffy, it blends right into the pumpkin without anyone knowing it’s there. I’ve had guests try to guess the ingredients more than once, and nobody has landed on cauliflower.
I’ve also tested half butternut squash in place of the pumpkin, and it gives the same warm, slightly sweet result. So if you can’t find canned pumpkin or just prefer squash, that’s a solid backup. Either way, each serving comes in at just 7.6 grams of total carbs and 2.2 grams net, making this one of the lightest keto side dishes on any holiday table.
A lot of classic recipes pile marshmallows on top, but I went with a buttery pecan crumble instead. Each marshmallow has about 4 grams of carbs, so cutting them was an easy call. The pecans give you that same crunchy, sweet contrast without the sugar. After testing both side by side, I actually prefer the pecan topping. There’s something about warm cinnamon and toasted nuts together that works better with the pumpkin base than a sticky marshmallow layer ever did.
One thing I didn’t expect: the broiler step at the end makes a huge difference. I used to skip it, thinking it was optional. But those 1-2 minutes under the broiler give the pecans a toasty, almost caramelized crunch that takes the whole dish up a level. Don’t skip it.
How many carbs are in traditional sweet potato casserole?
The classic version of this casserole is one of those dishes that looks innocent but packs a serious carb punch. A typical serving made with the traditional mashed filling, brown sugar, and marshmallows can hit 30 to 45 grams of total carbs per serving, depending on how heavy-handed you go with the toppings. I used to make it every Thanksgiving before going keto, and I never thought about the sugar content until I started reading labels.
Even without the marshmallows, the base itself is the main culprit. Once you add brown sugar, maple syrup, or that sticky marshmallow layer, the carb count goes through the roof. That’s exactly why I spent so long developing a low carb version using pumpkin and cauliflower instead. You still get that cozy, slightly sweet flavor without blowing your entire day’s carb budget on one side dish.
How to store and make this ahead
Make ahead instructions
One of the best things about this casserole (besides how it tastes) is how well it works for make-ahead prep. I prepare the filling and topping up to two days in advance, then cover and refrigerate until I’m ready to bake. When it’s time, I let it sit at room temperature for about 30 minutes so it heats evenly. This is a lifesaver during Thanksgiving when I’m juggling keto cornbread stuffing, pumpkin biscuits, and dessert all at once.
Freezer instructions
If you want to get even further ahead, this casserole freezes well. I assemble it completely but leave off the pecan topping so it stays crisp after baking. Wrap tightly in plastic wrap and aluminum foil, and it keeps frozen for up to two months. When you’re ready, thaw overnight in the fridge, add the topping, and bake as directed.
Leftovers keep in the fridge for up to 4 days and reheat fine in the oven or microwave. I usually give it just enough time to warm through without drying out.
How to make this casserole
Each serving has just 7.6 grams of total carbs and 2.2 grams net, and the whole recipe is naturally gluten-free. I’ve made it dairy-free by swapping the butter for coconut oil and using coconut cream instead of the cream cheese. My dairy-free version needs about 3 extra minutes in the oven to set up fully, but the texture stays creamy.
I blend everything until completely smooth so there are no chunks in the filling. If your food processor struggles with the volume, work in two batches. The filling should pour easily into the dish, not plop.
Preheat oven to 350 °F. Grease a medium casserole dish (e.g., 8 × 8 or similar) with butter.
2
Prepare cauliflower rice
To prepare cauliflower rice, heat a non-stick skillet over medium heat. Pour frozen cauliflower rice into the dry skillet. Stirring occasionally, cook over medium heat until the majority of the moisture has evaporated from the cauliflower and it is fluffy, about 7-10 minutes. Remove from heat.
For this step
12 oz bag frozen cauliflower rice
3
Make the filling
In a food processor or blender, combine the steamed cauliflower, pumpkin purée, butter, cream cheese, eggs, heavy cream, sweetener, cinnamon, nutmeg, and salt. Blend until smooth and creamy.
For this step
1 cup pumpkin puree
3 tablespoons unsalted butter
3 oz cream cheese
2 large eggs
2 tablespoons heavy whipping cream
3 tablespoons brown sugar substitute
1/2 teaspoon ground cinnamon
1/4 teaspoon ground nutmeg
1/4 teaspoon salt
4
Transfer to a dish
Transfer the mash mixture into the prepared casserole dish, smoothing the top.
5
Make pecan topping
Prepare the topping: In a small bowl, mix pecans, melted butter, brown-sugar substitute, and cinnamon. Sprinkle evenly over the mash.
For this step
1/3 cup chopped pecans
2 tablespoons unsalted butter, melted
1 tablespoon brown sugar substitute
1/2 teaspoon ground cinnamon
6
Bake
Bake for 25-30 minutes until the topping is lightly golden and everything is warmed through. Switch to broil and move dish under the top rack in the oven to broil on high for 1-2 minutes, watch carefully. Broil until lightly toasted.
Nutrition
Per serving: 1/12 of recipe
Calories
116
Fat
10.4g
Protein
2.3g
Total carbs
7.6g
Net carbs
2.2g
Nutrition is an estimate calculated from the ingredients listed. Brands vary, so check labels if you track closely.
Frequently Asked Questions
Are sweet potatoes keto friendly?
No, real sweet potatoes are too starchy to fit into a keto diet, which is why I don't use any in this casserole. If you're curious exactly how the carbs in the traditional version stack up, I break that down in the carb section above.
Can I use butternut squash instead of pumpkin?
Yes, and you don't have to stop at a half swap. Going all butternut squash makes the flavor a little more earthy than the pumpkin version, which I still like, though pumpkin is my go-to. Whichever way you go, cook the squash until it's very soft before blending so the filling stays smooth and creamy.
Can I make this casserole without eggs?
I've made it egg-free by using 2 tablespoons of ground flaxseed mixed with 5 tablespoons of water as a binder. The texture is slightly less firm than the egg version, but it still holds together and tastes great. My egg-free version sets up better after it cools for about 10 minutes before slicing.
What sweetener works best for this recipe?
I use a brown sugar substitute made with erythritol or allulose because it gives that caramelized, molasses-like flavor in both the filling and the pecan topping. Allulose is my preference since it doesn't crystallize, but erythritol works fine too. Plain granulated sweeteners will do the job if brown sugar subs aren't available, you'll just miss that deeper, toasty sweetness.
What can I use instead of cauliflower?
I've tried mashed turnips as a swap and they work, though the flavor is a bit more savory. The reason I stick with cauliflower is my dry-skillet method: cooking the rice for a full 7-10 minutes removes almost all the moisture and smell, so you genuinely can't taste it in the finished dish. If cauliflower is a dealbreaker for you, turnips are your best bet.
I run the cauliflower a little longer in the dry skillet than the recipe says, maybe an extra two minutes, and the filling sets up so much better. Batch four for me and that’s the only change I’ve stuck with.
Works fine with butternut squash, just give it a squeeze through a towel first if it seems watery, Maria. Flavor goes a bit more earthy than pumpkin but it still works.
Made this on Sunday because I had pumpkin puree sitting in the pantry and my daughter keeps asking for sweet potatoes. She’s 9 and she knows what a real sweet potato casserole tastes like, so I was ready for a fight. She ate her portion, went quiet for a minute, then came back and scooped up what was left in the dish before anyone else could get to it. That’s a review. The pecan topping is SO good, that buttery crunch against the creamy filling is what got me too.
Squeeze the cauliflower dry after steaming. I mean really wring it out in a kitchen towel until it stops releasing liquid. The filling was way less watery and actually held its shape after baking instead of spreading. I also toasted the pecans for 5 minutes before mixing them into the topping and the nuttiness got noticeably more intense against the cinnamon. Four stars for now because that dryness step should really be in the recipe, but with those two tweaks this is one of the better holiday-style sides I’ve made on keto.
The pecan topping is genuinely the best part of this, buttery and caramelized at the edges, and I’d double it next time without hesitation. The filling is good but the cauliflower comes through more than I expected, especially reheated the next day. Still making it again, just bumping the pumpkin puree and pulling it a minute or two early.
Tried two other keto casseroles before this and they both tasted too… healthy. The pumpkin with those buttery cinnamon pecans on top is what makes this one actually work.
The pumpkin is what sells it, not the cauliflower. I’ve made versions without it and they taste closer to mashed cauliflower than casserole. The pecan crumble is the closer.
Toasted the pecans dry in a cast iron pan before mixing them into the topping, and it was not a subtle difference. That deeper, almost smoky crunch layered on top of the cinnamon butter filling made me want to eat it straight out of the dish. I also ran the cauliflower in the food processor about 45 seconds past where I thought it was done, and the texture shifted completely, just this smooth, almost buttery base that stopped reading as cauliflower. My first batch was good. These two tweaks make it the version I keep. Going to try a drop of vanilla extract in the pecan mix next time and see if that pushes it even further.
so I used the frozen cauliflower rice like the recipe says and I was genuinely not sure blending it in the food processor was going to produce anything that looked like a casserole base but it came out looking completely normal and I was kind of shocked. I also added just a tiny pinch of extra cinnamon because I always overdo cinnamon on everything and I think it made the whole thing warmer without going overboard. my only tip for anyone new to this: do not skip draining the cauliflower after steaming or the whole thing gets watery, which I found out the hard way on my first attempt
Made the watery version once too. Now I do a dry-skillet for 7-8 minutes after steaming and it gets almost all the moisture out. Extra cinnamon with the nutmeg works.
Made a full batch on Sunday and portioned it out for the week. The pecan topping somehow stays crispy even after reheating, which I wasn’t counting on. Works right into my macros without any adjustments.
My husband has a whole thing about sweet potato casserole. He was halfway through his before I mentioned the cauliflower and pumpkin. He just nodded. Good enough for me.
Tried steaming fresh florets instead of frozen rice and the mash came out way smoother. Takes longer to get the moisture out in the skillet, but the texture in the casserole is cleaner. Worth it if you have fresh on hand.
Fresh florets give a cleaner mash, you’re right. The extra skillet time is worth it. I push mine to 12-13 minutes when I use fresh to get the moisture fully out.
Made this Sunday and my sister (who has exactly zero interest in keto) kept picking at the pecan topping after dinner asking what was in it. She was convinced I used real sweet potato. The pumpkin and cauliflower blend so smooth you’d never know.
Non-keto people are the hardest ones to fool. The dry skillet step is what makes it blend that smooth (microwaved frozen cauliflower stays too watery and you can tell).
