This light, airy Butternut Squash Casserole is a cozy, festive side dish for your holiday table. Homemade butternut squash purée gives the filling a silky, fresh flavor and a superior texture compared with canned purée, and the oat-pecan streusel adds a satisfying crunch. The casserole can be prepped ahead—purée up to three days in advance and assemble the casserole a day ahead—so you can enjoy more time with guests.
The holidays are a perfect time to savor seasonal flavors. Butternut squash is a pantry favorite in autumn and winter because it’s versatile, mildly sweet, and pairs beautifully with warm spices and maple. When roasted and puréed, it becomes silky and light, making it ideal for casseroles, soups, and baked goods.
This Butternut Squash Casserole is similar in spirit to a classic sweet potato casserole but lighter in texture and flavor. The maple-sweet filling is balanced by cinnamon and vanilla, while the streusel—made with oats, pecans, and brown sugar—adds texture and nutty depth. You can also make simple swaps to accommodate dietary needs, like using vegan butter and gluten-free flour.
Why you’ll love this recipe:
- Light, fluffy texture from homemade butternut squash purée with warm maple and cinnamon flavors.
- Oat-pecan streusel topping for a crunchy, wholesome contrast to the creamy filling.
- Make-ahead friendly: purée can be made up to 3 days ahead; the assembled casserole can be prepared a day in advance.
- Easy to adapt to dairy-free and gluten-free diets with simple ingredient swaps.
Recipe ingredients
These straightforward ingredients transform into a festive side dish. You can customize amounts and swaps to suit tastes and dietary needs.
- Butternut squash: Roast and purée for the best flavor and texture. Homemade purée can be made up to 3 days ahead and drained to remove excess liquid for a thicker filling.
- Maple syrup: Adds classic fall flavor; honey or another liquid sweetener can be used instead.
- Butter and milk: Use vegan butter and a non-dairy milk for a dairy-free version. Full-fat milk adds more richness.
- Flour: Use all-purpose flour for the streusel or substitute a 1-to-1 gluten-free flour or a mix of oat and almond flours.
- Old-fashioned oats: Give the streusel a chewy texture when baked.
- Brown sugar: Swap coconut sugar for a refined-sugar-free option.
- Pecans: Provide crunch and flavor; swap walnuts or omit for nut-free needs.
See the recipe card below for precise quantities and the full ingredient list.
How to make this recipe
The recipe has three parts: roast and purée the squash, mix the filling, and prepare the streusel. Each step is simple and many components can be done ahead.
Pro tip: Making your own squash purée elevates the casserole—it’s worth the extra time. Roast the squash, purée it smooth, then drain overnight in the refrigerator to remove excess liquid for the best texture.
Full step-by-step instructions are included in the recipe card below.
- Preheat the oven and roast halved butternut squash until tender. Scoop out the flesh and purée until smooth.
- Drain the purée in a fine mesh sieve lined with cheesecloth in the refrigerator overnight to remove excess liquid.
- Beat the drained squash purée with eggs, maple syrup, milk, softened butter, cinnamon, vanilla, and salt until combined.
- Pour the filling into a greased baking dish.
- For the streusel, mix oats, flour, brown sugar, pecans, cinnamon, cardamom, and a pinch of salt. Cut in cold butter until pea-sized clumps form.
- Sprinkle the streusel evenly over the filling and bake at 350°F for about 45 minutes, until the streusel is golden and the center is set.
- Cool briefly on a wire rack before serving.
Recipe FAQs
Butternut squash purée is mildly sweet, similar to a cross between pumpkin and sweet potato. It’s smoother and lighter than mashed sweet potato and sweeter than pumpkin, which makes it versatile in both savory and sweet recipes.
Canned purée works in a pinch and saves time, but homemade purée typically has a fresher flavor and thicker texture that improves the final dish.
Store purée in the refrigerator for up to 3 days or freeze for up to 3 months.
Both are nutritious sources of vitamins, fiber, and beta-carotene. Butternut squash tends to be lower in calories and carbohydrates, which may appeal to those watching carb intake.
Serving suggestions
This casserole shines as a holiday side but is equally welcome at any fall or winter meal.
- Serve it alongside roast turkey, glazed ham, or pork chops for a comforting holiday plate.
- Bring it to Friendsgiving or a potluck—it’s easy to reheat and travels well when fully cooled.
- For a weeknight meal, pair it with roasted vegetables and a simple green salad for a vegetarian option.
Recipe notes
- Make ahead: Roast and purée the squash up to 3 days ahead. Drain the purée overnight for best results. Assemble the casserole the day before and bake when ready.
- Dairy- and gluten-free options: Use vegan butter and a non-dairy milk for dairy-free. Substitute all-purpose flour with a 1:1 gluten-free blend or a mix of oat and almond flours for a gluten-free streusel.
- Sugar swaps: Replace maple syrup with honey or another liquid sweetener. Use coconut sugar in the streusel to avoid refined sugar.
- Storage: Refrigerate leftovers for 3–5 days and reheat gently.
More butternut squash recipes you’ll love:
- Butternut squash mac and cheese
- Butternut squash quinoa salad
- Mashed butternut squash
- Roasted whole butternut squash and tips for peeling and cutting
Did you try this recipe? If so, leave a review below and share how you served it.
Butternut Squash Casserole with Streusel Topping
Servings: 12
Prep Time: 30 mins • Cook Time: 1 hr 20 mins • Drain Time: 8 hrs • Total Time: 9 hrs 50 mins
Equipment
- Rimmed baking sheet
- Food processor
- Fine mesh sieve and cheesecloth
- 8×8″ baking dish
Ingredients
For the casserole:
- 1 tablespoon oil
- 1 large butternut squash, halved and seeds removed
- 4 large eggs
- 1/3 cup pure maple syrup
- 1/2 cup milk (dairy or non-dairy)
- 4 tablespoons unsalted butter, softened
- 2 teaspoons ground cinnamon
- 2 teaspoons vanilla extract
- 1/2 teaspoon salt
For the streusel:
- 1/2 cup old-fashioned rolled oats
- 1/2 cup all-purpose flour (or gluten-free 1:1 blend)
- 1/3 cup light brown sugar, packed
- 1/2 cup pecan pieces
- 1 teaspoon ground cinnamon
- 1/4 teaspoon sea salt
- 6 tablespoons unsalted butter, cold and cubed
Instructions
Prepare the casserole:
- Preheat oven to 375°F. Line a rimmed baking sheet with foil. Rub squash halves with oil, place cut side down, and roast 35–45 minutes until fork tender.
- When cool enough to handle, scoop the flesh and purée in a food processor until smooth (about 4–4½ cups purée).
- Transfer purée to a fine mesh sieve lined with cheesecloth over a bowl. Cover and refrigerate overnight to drain excess liquid.
- Preheat oven to 350°F and grease an 8×8″ baking dish. Beat drained purée with eggs, maple syrup, milk, butter, cinnamon, vanilla, and salt until smooth. Pour into the dish.
Prepare the streusel:
- Combine oats, flour, brown sugar, pecans, cinnamon, and salt in a bowl.
- Cut in cold butter with a pastry blender or fork until pea-sized clumps form.
- Sprinkle streusel over the filling and bake at 350°F for about 45 minutes, until golden and set.
- Cool on a wire rack for 10 minutes, then serve.
Notes
- Make-ahead: Roast and purée the squash ahead of time. Drain overnight and proceed with the recipe when ready.
- Allergy swaps: Use vegan butter and non-dairy milk for dairy-free; swap flour for gluten-free blends as needed.
- Leftovers: Refrigerate for 3–5 days and reheat gently.
Nutrition
Serving: 1 • Calories: 235 kcal • Carbohydrates: 24 g • Protein: 5 g • Fat: 14 g • Saturated Fat: 6 g • Polyunsaturated Fat: 7 g • Cholesterol: 83 mg • Sodium: 133 mg • Fiber: 2 g • Sugar: 11 g
Nutrition is estimated and intended as a guideline.
Note: This recipe was originally published in November 2015. Photos and instructions have been updated for clarity and ease of use.