This Keto Sweet Potato Casserole brings all the cozy holiday flavor without the carb crash. We lean on roasted butternut, cauliflower, and a touch of pumpkin for a creamy, spiced base, then finish with a buttery pecan streusel. It tastes like the classic everyone loves, just keto friendly.
Keto Sweet Potato Casserole with Pecan Streusel Topping
Equipment
- 2 Sheet pan parchment lined
- 1 Parchment Paper for lining pans
- 1 Food processor or blender
- 1 Mixing Bowl
- 1 2-quart baking dish
- 1 Broiler (optional)
Ingredients
Base
- 1 lb butternut squash peeled and cubed (about 3 heaping cups)
- 1 lb cauliflower florets (about 5 cups)
- 1 tbsp avocado oil or olive oil
- 0.5 cup unsweetened pumpkin puree
- 2 large eggs room temperature
- 3 tbsp unsalted butter melted (or ghee)
- 0.25 cup heavy cream or full fat coconut milk
- 0.33 cup granulated monkfruit erythritol or to taste
- 1 tsp vanilla extract
- 1.5 tsp ground cinnamon
- 0.25 tsp ground nutmeg
- 0.125 tsp ground cloves or allspice
- 0.5 tsp fine sea salt
Pecan Streusel Topping
- 1 cup pecans chopped
- 0.5 cup blanched almond flour
- 0.33 cup brown sugar substitute keto brown sweetener
- 3 tbsp unsalted butter melted
- 0.5 tsp ground cinnamon
- fine sea salt pinch
Instructions
Steps
- Heat oven to 425 F. Toss cubed butternut and cauliflower with oil and a pinch of salt. Spread on 2 parchment lined sheet pans and roast 25 to 30 minutes, stirring once, until tender and lightly caramelized. Reduce oven to 350 F.
- Transfer roasted vegetables to a food processor or blender. Add pumpkin puree, melted butter, cream, granulated sweetener, vanilla, cinnamon, nutmeg, cloves, and salt. Pulse until very smooth. Let the mixture sit 3 to 5 minutes so it is warm, not hot. Add eggs and blend just until combined. Taste and adjust sweetness or salt.
- Grease a 2 quart baking dish. Spread the mash into an even layer and smooth the top.
- In a bowl, stir almond flour, brown sweetener, cinnamon, and salt. Drizzle in melted butter and mix until crumbles form. Fold in pecans.
- Scatter streusel evenly over the casserole. Bake at 350 F for 25 to 30 minutes until the center is just set and the topping is fragrant. If desired, broil 1 to 2 minutes to toast the pecans. Watch closely.
- Let cool 10 to 15 minutes so the custard sets. Spoon into bowls and enjoy warm.
Notes
Nutrition
Why You’ll Love This Keto Sweet Potato Casserole
- Classic flavor, keto ingredients that mimic sweet potatoes beautifully.
- Silky, custardy base with a crisp, buttery pecan topping.
- Simple, whole-food ingredients and easy steps.
- Make ahead friendly for stress free holidays.
- Naturally gluten free with dairy free and nut free options.
Keto Sweet Potato Casserole Ingredients & Substitutions
Base
- 1 lb butternut squash, peeled and cubed (about 3 heaping cups)
- 1 lb cauliflower florets (about 5 cups)
- 1 tbsp avocado or olive oil
- 1/2 cup unsweetened pumpkin puree
- 2 large eggs, room temperature
- 3 tbsp unsalted butter, melted (or ghee)
- 1/4 cup heavy cream or full fat coconut milk
- 1/3 cup granulated monkfruit erythritol, or to taste
- 1 tsp vanilla extract
- 1 1/2 tsp ground cinnamon
- 1/4 tsp ground nutmeg
- 1/8 tsp ground cloves or allspice
- 1/2 tsp fine sea salt
Pecan Streusel Topping
- 1 cup chopped pecans
- 1/2 cup blanched almond flour
- 1/3 cup brown sugar substitute
- 3 tbsp unsalted butter, melted
- 1/2 tsp ground cinnamon
- Pinch fine sea salt
Substitutions
- No butternut: use all cauliflower and add 2 to 3 tbsp extra pumpkin for color and sweetness.
- Dairy free: use coconut milk for cream and coconut oil for butter.
- No nuts: swap almond flour with sunflower seed flour and pecans with toasted pepitas or coconut flakes.
- Sweeteners: allulose gives a softer set and less crystallization; erythritol blends can taste sweeter. Adjust to taste.
Step-by-Step Instructions to Make Keto Sweet Potato Casserole
Step 1: Roast the vegetables
Heat oven to 425 F. Toss cubed butternut and cauliflower with oil and a pinch of salt. Spread on 2 parchment lined sheet pans and roast 25 to 30 minutes, stirring once, until tender and lightly caramelized. Reduce oven to 350 F.
Step 2: Blend the silky base
Transfer roasted vegetables to a food processor or blender. Add pumpkin puree, melted butter, cream, granulated sweetener, vanilla, cinnamon, nutmeg, cloves, and salt. Pulse until very smooth. Let the mixture sit 3 to 5 minutes so it is warm, not hot. Add eggs and blend just until combined. Taste and adjust sweetness or salt.
Step 3: Assemble the casserole
Grease a 2 quart baking dish. Spread the mash into an even layer and smooth the top.
Step 4: Make the pecan streusel
In a bowl, stir almond flour, brown sweetener, cinnamon, and salt. Drizzle in melted butter and mix until crumbles form. Fold in pecans.
Step 5: Bake until set
Scatter streusel evenly over the casserole. Bake at 350 F for 25 to 30 minutes until the center is just set and the topping is fragrant. If desired, broil 1 to 2 minutes to toast the pecans. Watch closely.
Step 6: Rest and serve
Let cool 10 to 15 minutes so the custard sets. Spoon into bowls and enjoy warm.
Tips for Success
- Roast, do not steam. Dry heat concentrates flavor and prevents watery mash.
- Let steam escape. After blending, pause a few minutes before adding eggs to avoid curdling.
- Smoother texture. Process 60 to 90 seconds for an ultra silky base.
- Sweetener notes. Erythritol can crystallize when chilled. For make ahead, use part allulose for a softer set.
- Toasty pecans. If you skip broiling, toast pecans 5 minutes at 350 F before mixing into streusel.
- Dairy free. Use coconut milk and coconut oil or ghee with great results.
- Make ahead. Assemble base and keep topping separate. Refrigerate up to 24 hours. Add topping and bake, adding 5 to 10 extra minutes.
Variations of Keto Sweet Potato Casserole
- Marshmallow style: top with keto marshmallows during the last 5 minutes.
- Bacon maple pecan: fold 1/3 cup crisp crumbled bacon into the streusel and drizzle with 1 to 2 tsp keto maple syrup after baking.
- Nut free crunch: use sunflower seed flour in the topping and swap pecans for pepitas or toasted coconut.
- Extra silky: blend in 1 oz cream cheese with the base.
- Orange spice: add 1 tsp grated orange zest and a pinch of ginger to the base.
Serving Suggestions: What to Pair with Keto Sweet Potato Casserole
- Roast turkey, herb roasted chicken, or glazed ham for a holiday spread.
- Crispy roasted Brussels sprouts or garlicky green beans.
- A bright salad with lemon vinaigrette to cut the richness.
- Breakfast twist: top leftovers with a fried egg and a dash of hot sauce.
Storage & Reheating Instructions
- Refrigerate: Cover and chill up to 4 days.
- Freeze: Best frozen without the topping, up to 3 months. Or freeze leftovers in portions.
- Reheat: 325 F for 15 to 20 minutes until warm. Air fryer 350 F for 4 to 6 minutes to re crisp the topping. Microwave in 30 second bursts for quick servings.
Memories Made Around the Table
I first served this for a keto Thanksgiving when my aunt swore she would miss the real thing. She went back for seconds and asked for the recipe before dessert. That is when I knew it was a keeper.
FAQs
Is this really keto without sweet potatoes?
Yes. Roasted butternut, cauliflower, and a little pumpkin create the same creamy, spiced vibe with a fraction of the carbs.
How many carbs per serving?
For 8 servings, estimate about 8 g net carbs, 24 g fat, 6 g protein, and roughly 260 calories per serving. Exact macros vary by brands.
Can I make it without nuts?
Absolutely. Use sunflower seed flour in place of almond flour and swap pecans for toasted pepitas or coconut flakes.
What sweetener works best?
Brown style allulose or erythritol monkfruit blends taste great. Allulose stays soft, while erythritol can recrystallize when chilled.
Can I make it egg free?
Use a flax egg mix 2 tbsp ground flax with 6 tbsp water. The texture will be a bit softer but still delicious.
Final Thoughts
This Keto Sweet Potato Casserole delivers the nostalgic comfort you crave with smart, low carb swaps. Make it for the holidays or any cozy Sunday dinner and watch it disappear.