The Washington Post

Winter Squash Gratin

Winter Squash Gratin 4.000

Tom McCorkle for The Washington Post; food styling by Lisa Cherkasky for The Washington Post

Instant Pot Nov 13, 2018

For this casserole, which could serve as main course for vegetarians at Thanksgiving, the squash is quickly steamed in the multicooker/electric pressure cooker (6-quart capacity, with a steaming rack), then blended with egg yolks for richness and whipped egg whites that lighten the texture.

We tested it with butternut squash, but just about any type of winter squash would work here. Orange zest adds a note of sunshine, but you could omit all the seasoning except for salt and pepper and the flavor would still satisfy. You will need a 6-cup, shallow baking dish.

Grated cheese turns the top golden and crusty, but if you’re not in the mood, feel free to just dot the top with butter instead.

Make Ahead: The squash can be cooked, cooled and refrigerated up to 4 days in advance. The casserole can be assembled, covered and refrigerated a day before it is baked.

4 - 6

When you scale a recipe, keep in mind that cooking times and temperatures, pan sizes and seasonings may be affected, so adjust accordingly. Also, amounts listed in the directions will not reflect the changes made to ingredient amounts.

Tested size: 4-6 servings

  • 2 pounds winter squash, such as butternut or kabocha (see headnote)
  • 4 tablespoons (1/2 stick) unsalted butter, melted, plus more as needed
  • 1/4 cup dried bread crumbs
  • 3/4 cup whole milk
  • 4 large eggs
  • 1/2 teaspoon fine salt
  • 1/2 teaspoon freshly grated nutmeg (optional)
  • 2 tablespoons finely grated orange zest (optional)
  • Freshly ground black pepper
  • 1/4 cup grated Comté or Gruyère cheese (optional)


Slice the squash into 1-inch-thick rings or wedges and seed them, as needed.

Place the steaming rack in the pressure cooker and add 1 cup water. Arrange the squash on the rack. Cook on high pressure for 12 minutes.

While the squash is cooking, generously grease a shallow 6-cup baking dish with butter, then coat with the bread crumbs.

Once the squash is done, manually release the steam. Transfer the squash to a plate to cool slightly. Preheat the oven to 400 degrees.

Use a spoon to scrape the flesh from the tough skin; discard the skin. Transfer the flesh to a blender or food processor and puree (or use an immersion, or stick, blender). Transfer the squash to a mixing bowl; add the 4 tablespoons of melted butter, the milk, 2 of the eggs, the salt, and the nutmeg and orange zest. Season lightly with pepper.

Separate the remaining 2 eggs into whites and yolks, adding the yolks to the squash mixture, and place the whites in a separate large bowl. Combine the egg yolks with the squash mixture, stirring until well incorporated.

Add a pinch of salt to the egg whites and beat with a whisk or handheld mixer until they hold stiff peaks. Fold the egg whites into the squash mixture, leaving some streaks of white.

Gently pour the squash mixture into the prepared baking dish. Sprinkle the grated cheese over the top, if using (or dot the surface with small bits of 1 tablespoon of unsalted butter). Bake for 40 to 50 minutes, until the top is golden and the center looks set. Serve warm.

Recipe Source

Adapted from Ann Mah, author of "Instantly French! Classic Recipes for Your Electric Pressure Cooker" (St. Martin’s Griffin, 2018). CORRECTION: An earlier version of this recipe gave the incorrect amount of carbohydrates in its nutritional analysis.

Tested by Diana Maxwell.

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Nutritional Facts

Calories per serving (based on 6): 190

% Daily Values*

Total Fat: 12g 18%

Saturated Fat: 7g 35%

Cholesterol: 145mg 48%

Sodium: 280mg 12%

Total Carbohydrates: 15g 5%

Dietary Fiber: 2g 8%

Sugar: 4g

Protein: 7g

*Percent Daily Value based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

Total Fat: Less than 65g

Saturated Fat: Less than 20g

Cholesterol: Less than 300mg

Sodium: Less than 2,400mg

Total Carbohydrates: 300g

Dietary Fiber: 25g

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