Let me be straight with you about what is in this dish, because it surprises people. The filling is mostly cauliflower. 330g of steamed cauliflower does the work that mashed sweet potato usually does in a traditional casserole, and the sweet potato is 120g, there for flavor and color rather than as the star.
Blended smooth, it tastes like sweet potato casserole. It is orange, it is creamy, and the cinnamon and pecan streusel on top finish the argument.
That swap is what keeps a no-added-sugar sweet potato pecan casserole at about 140 calories and 5g net carbs per serving instead of the calorie count of the dessert classic. Greek yogurt and whey isolate give it the creamy body and 8g of protein, and granulated allulose sweetens without the syrupy aftertaste. Prep takes 20 minutes, it bakes 30 to 35 minutes, and it needs 10 to 15 minutes to rest before it will hold its shape on a spoon.
Eight servings, and it is the kind of side dish that quietly disappears first. There is no refined sugar anywhere in it, and nothing depends on a specialty ingredient beyond allulose. If you are still deciding how allulose behaves in a warm bake, my guide to sugar-free sweeteners for baking lays out the differences that matter.
Why You’ll Love This Recipe
This no-added-sugar sweet potato pecan casserole keeps the two parts people actually remember, the creamy orange filling and the pecan topping, and gets the base from something most holiday tables never use.
- It still tastes like sweet potato casserole. The sweet potato flavor is real, the color is right, and the cinnamon and vanilla land the way you expect. Nobody at the table is told what the base is.
- Creamy without a cream sauce. Thick 0% Greek yogurt and unflavored whey isolate blend into the cauliflower until the filling is completely smooth and scoopable.
- An abundant pecan topping. Pecan halves and coarse pieces go on by the handful, so the streusel looks like a proper holiday topping and each bite has nuts in it.
- About 140 calories and 5g net carbs a serving. Eight servings with 8g protein and 4g fiber each.
- One dish, one blender, 50 minutes. Everything goes into the same 8×8-inch ceramic dish, and there is no separate topping to bake on a sheet pan.
Ingredient Notes
For the creamy filling
Here is the honest breakdown of the filling. Steamed cauliflower, squeezed very dry (2¾ cups, 330g) is the bulk of it, and it replaces the volume that sweet potato would normally provide.
Cooked mashed sweet potato (½ cup plus 2 tbsp, 120g) is the smaller share. It is there for the flavor and the orange color, and the ratio matters: if you double the sweet potato, you double the carbs, and if you drop it, you lose the flavor that makes this taste like the holiday dish rather than a cauliflower bake.
How dry the cauliflower is decides the whole texture, and this is the one step worth obsessing over. Steam it, let it cool enough to handle, then squeeze it hard in a clean towel until nothing drips out.
Cauliflower carries water in its florets, and any of that water left behind shows up as a thin, watery layer at the bottom of the dish. Raw cauliflower values vary enough by preparation that USDA FoodData Central lists cauliflower on its own if you want the numbers for your own batches.
Thick plain 0% Greek yogurt (½ cup, 120g) is the creaminess, and thickness matters more here than in a cheesecake. Unflavored whey isolate (¼ cup, 20g) blends in without adding sweetness, oat fiber (1 tbsp, 8g) gives the filling a little structure so it scoops instead of spreading, and two large eggs (100g) are what set it in the oven. Melted unsalted butter (2 tsp, 10g), granulated allulose (3 tbsp, 30g), cinnamon (1 tsp), alcohol-free vanilla (½ tsp), and salt (¼ tsp) round it out.
For the pecan streusel
Pecan halves and coarse pieces (⅓ cup, 45g) are the point of this topping, so chop or break them irregularly rather than pulsing them fine. You want visible nuts in the finished dish, not a uniform brown layer.
Almond flour (3 tbsp, 20g) and oat fiber (1 tbsp, 8g) give the crumbs structure, granulated allulose (1½ tbsp, 18g) browns them in the oven, and softened unsalted butter (1 tbsp, 14g) is what you work in with your fingertips until the mixture holds together in moist, uneven clumps. A little cinnamon and a pinch of salt finish it.
How to Make It
Step 1: Heat the oven and grease the dish
Heat the oven to 350°F and grease the 8×8-inch ceramic baking dish. A straight-sided square dish matters more than it sounds, because the filling is thick and a dish with rounded corners leaves you with an uneven scoop. Give the dish a real coating of grease, not a pass with a paper towel.
Step 2: Squeeze the cauliflower dry
Steam the cauliflower until tender, then let it cool enough to handle. Put it in a clean kitchen towel and squeeze as hard as you can over a bowl. You should be able to wring out a surprising amount of water.
When the towel stops dripping and the florets feel dry and heavy in your hand, they are ready. Skipping this is the most common reason a cauliflower-based casserole ends up loose and watery.
Step 3: Blend the filling until smooth
Add the squeezed cauliflower to a blender along with the cooked mashed sweet potato, thick Greek yogurt, unflavored whey isolate, oat fiber, melted butter, granulated allulose, cinnamon, alcohol-free vanilla, and salt. Blend until completely smooth, then rest the puree for 3 minutes. That rest lets the oat fiber and the whey hydrate, which thickens the filling and gives you something closer to mashed sweet potato than to a dip.
Step 4: Spread it into the dish
Smooth the filling evenly into the greased dish, all the way to the corners. Level the top with the back of a spoon so it sits flat under the streusel. If you want a cleaner edge, wipe the rim of the dish with a damp finger before the topping goes on.
Step 5: Make the pecan streusel
Put the pecan halves and coarse pieces, almond flour, oat fiber, granulated allulose, and cinnamon in a bowl with the pinch of salt. Add the softened butter and work it in with your fingertips.
Stop when the mixture forms irregular moist crumbs. You are looking for clumps of different sizes, not a uniform sand, and not a paste.
Step 6: Scatter and bake
Scatter the streusel over the filling, keeping several large pecan pieces visible on the surface. Push the biggest halves on top so they toast instead of sinking. Bake at 350°F for 30 to 35 minutes, until the edges are set, the center is softly firm, and the pecans are toasted.
Step 7: Broil and rest
If the top needs more color, put it under the broiler for 30 to 60 seconds and watch it the entire time. Allulose browns fast, and streusel goes from toasted to burned inside half a minute. Then rest the dish for 10 to 15 minutes before serving, which lets the filling firm up enough to scoop cleanly.
Success Tips
- Cauliflower must be very dry to prevent watery filling. Squeeze it in a towel until nothing drips. This is the step that decides whether the dish is creamy or loose.
- Blend until no cauliflower pieces remain visible. Even a small fleck of raw-looking cauliflower reads as a vegetable, not as a side dish. Take the extra 30 seconds.
- Keep pecans coarse and irregular for an abundant topping. Halves and big pieces make the top look generous and give you a whole nut in some spoonfuls.
- Do not overbake; filling should stay creamy and scoopable. Pull it when the edges are set and the center is softly firm. It keeps firming as it rests, so it will be scoopable rather than set like a pudding.
- Watch the broiler. Thirty seconds is usually enough with allulose in the streusel. Stand there for the whole minute.
Storage
This recipe comes without a tested shelf-life, so plan to eat the no-added-sugar sweet potato pecan casserole the day it is baked or the next. Cover it and keep it refrigerated, and let it come back toward room temperature for about 20 minutes before serving so the filling softens. The streusel will soften in the fridge, which is normal, and it can be refreshed briefly under the broiler if you want the top back.
The filling is egg- and yogurt-based, so it should not sit at room temperature for long. If you are making it ahead for a holiday table, do the blending and the dish assembly a day early, keep it chilled and unbaked, and bake it fresh. That also means the topping goes on at the last moment and stays crisp.
No-Added-Sugar Sweet Potato Pecan Casserole FAQ
Is this really sweet potato casserole, or mostly cauliflower?
It is mostly cauliflower by weight, 330g to 120g. This no-added-sugar sweet potato pecan casserole gets its sweet potato flavor and its orange color from that smaller share. It tastes like sweet potato casserole, but if you are expecting a mash made entirely from sweet potatoes, this is a different, lighter version of the dish.
Why is my casserole watery?
Cauliflower that was not dry enough. The florets hold a surprising amount of water, and it migrates into the filling during the bake.
Squeeze the steamed cauliflower in a towel until the towel stops dripping. The other cause is overblending with a lot of thin liquid, which is another reason the recipe calls for thick yogurt rather than runny.
Can I use frozen cauliflower?
Yes, and it works well, as long as you thaw and squeeze it properly. Thaw it in the fridge rather than the microwave so it does not go waterlogged, then squeeze it dry the same way. Thawed frozen cauliflower often releases more water than freshly steamed, so give it an extra thorough wring.
How do I know when it is done?
At 30 to 35 minutes at 350°F the edges should be set, the center softly firm rather than liquid, and the pecans visibly toasted. If the center still ripples when you nudge the dish, give it a few more minutes. Do not wait for the whole surface to look dry, or the filling goes from creamy to bakes firm.
Can I make the streusel ahead of time?
Yes. Mix the streusel and keep it sealed and cool, then scatter it on right before the casserole goes in the oven.
The butter in it needs to stay cold for the crumbs to stay irregular. If you mix it too far in advance and it warms up, you will get a more uniform, slightly greasy layer instead of coarse crumbs.
Knowing the filling is mostly cauliflower makes this easier to plan, not harder. Steam it, squeeze it dry, blend it smooth, and you have a creamy side that lands at about 140 calories a serving.
For another baked dish with the same no-added-sugar logic and a spiced sauce on top, the no-added-sugar apple chutney chicken is a good one, and the no-added-sugar smoky BBQ sauce explains the allulose behavior this streusel depends on. For the savory side of the table, the no-added-sugar green bean casserole builds its creamy center from a homemade Neufchatel-Parmesan sauce instead of a can of cream-of-mushroom soup, and browns a thin almond flour crumb where the fried onion rings usually go.
No-Added-Sugar Sweet Potato Pecan Casserole
Ingredients
Equipment
Method
- Heat oven to 350°F. Grease baking dish.
- Squeeze cooked cauliflower extremely dry.
- Blend all filling ingredients until completely smooth; rest 3 min.
- Spread evenly into dish.
- Mix streusel ingredients, working in butter until irregular moist crumbs form.
- Scatter over filling, keeping several large pecan pieces visible.
- Bake 30–35 min until edges set, center is softly firm, and pecans are toasted.
- Broil 30–60 sec only if extra browning is needed. Rest 10–15 min.
Notes
- Cauliflower must be very dry to prevent watery filling.
- Blend until no cauliflower pieces remain visible.
- Keep pecans coarse and irregular for an abundant topping.
- Do not overbake; filling should stay creamy and scoopable.