Yellow Summer Squash Soufflé

Squash souffle
Diana Rattray
Prep: 10 mins
Cook: 30 mins
Total: 40 mins
Servings: 6 servings
Nutrition Facts (per serving)
465 Calories
27g Fat
38g Carbs
20g Protein
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Nutrition Facts
Servings: 6
Amount per serving
Calories 465
% Daily Value*
Total Fat 27g 34%
Saturated Fat 14g 70%
Cholesterol 134mg 45%
Sodium 739mg 32%
Total Carbohydrate 38g 14%
Dietary Fiber 4g 15%
Protein 20g
Calcium 493mg 38%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

This popular summer squash casserole—or soufflé—makes an excellent Sunday dinner or holiday side dish. The casserole bakes to perfection with a buttery breadcrumb topping. The casserole is a fast and easy preparation, taking no more than 15 minutes. 

The squash soufflé is tasty, but if you crave more flavor and color, consider adding some other vegetables to the dish. Shredded carrots make a good addition to the squash; add them to the saucepan along with the sliced squash and chopped onion. Or stir some finely chopped red and green bell pepper into the mashed squash mixture. Another option for the dish is zucchini. Use part or all zucchini in the casserole along with yellow summer squash, or use another variety of summer squash, such as ​pattypan or the pale green cousa squash. 

You can vary the topping as well. Instead of breadcrumbs, toss saltine or cheese cracker crumbs with the butter. Or top the casserole with crumbled French fried onion rings. Add some extra shredded cheese—or save about 1/2 cup out of the 2 cups—to the top along with the crumbs if you'd like.


  • 2 pounds yellow summer squash (3 to 4 medium)
  • 1 medium onion
  • 1 teaspoon kosher salt
  • 1/2 teaspoon  seasoned salt (or to taste)
  • 1/4 teaspoon ground black pepper (or to taste)
  • 1 cup milk
  • 2 large eggs
  • 3 tablespoons flour
  • 4 tablespoons melted butter (divided)
  • 2 cups/8 ounces cheddar cheese (shredded)
  • 1/2 cup fine dry breadcrumbs (or fresh processed breadcrumbs)

Steps to Make It

  1. Rinse the squash well and then pat dry with paper towels. Cut off and discard the ends of the squash. Slice the squash into 1/2-inch rounds. 

  2. Peel the onion. Cut off and discard the root end. Cut the onion in half and chop it finely

  3. Combine the sliced squash and chopped onion in a large saucepan. Cover the vegetables with water and add 1 teaspoon of kosher salt.

  4. Place the saucepan over high heat and bring to a boil. Reduce the heat to medium-low, cover the pan, and cook for about 15 minutes, or until the squash is very tender. 

  5. Preheat the oven to 350 F.

  6. Butter a 2-quart baking dish or casserole.

  7. Drain the squash and onions thoroughly and transfer them to a bowl; mash well. Taste and add seasoned salt and pepper, as desired.

  8. In a medium bowl, whisk the eggs with the milk, flour, and 3 tablespoons of melted butter. Add the cheese and stir until well blended.

  9. Combine the egg and milk mixture with the mashed squash mixture.

  10. Spoon the mixture into the prepared baking dish.

  11. Bake the squash casserole for about 30 minutes.

  12. Combine the breadcrumbs with the remaining butter and sprinkle them over the top of the casserole. Return the casserole to the oven and bake for about 10 minutes longer.


 If your squash is an older, large one with large seeds and tough skin, scoop out the seeds and peel the squash. Dice or slice it.