Cheesy Spinach Casserole
A creamy, protein-packed casserole featuring tender spinach, cottage cheese, Gruyère, and Parmesan. Ready in 40 minutes and perfect as a side dish or make-ahead meal.
Instructions
- Preheat oven to 375°F.
- Sauté aromatics: Melt butter in a large skillet over medium heat. Add chopped onion and cook for 3 minutes until soft and translucent. Add minced garlic, Italian seasoning, salt, pepper, and red pepper flakes. Stir for 1 minute.
- Wilt spinach: Add fresh baby spinach in batches, stirring gently and allowing each batch to wilt before adding more. Cook for about 5 minutes total until all spinach is wilted.
- Drain excess moisture: Using a slotted spoon, transfer the spinach mixture to a mixing bowl, leaving excess liquid behind in the skillet.
- Mix cheese and egg: Add cottage cheese to the spinach mixture. Reserve half of the Gruyère and half of the Parmesan for topping. Mix the remaining cheeses into the spinach. Crack in the egg and stir until well combined.
- Assemble casserole: Spread the mixture evenly into an 8x8 inch (or 1.5-2 quart) ceramic baking dish. Smooth the top with a spatula. Sprinkle reserved Gruyère and Parmesan evenly over the top.
- Bake: Place in preheated oven and bake for 25 minutes, or until bubbling around the edges and the cheese on top is golden brown.
- Rest and serve: Let casserole rest for 5 minutes before serving.
Notes
Frozen Spinach: Use 10 ounces frozen spinach. Thaw completely and squeeze out all excess water using a clean kitchen towel before using.
Cheese Substitutions: Swiss cheese, Fontina, or aged white cheddar can substitute for Gruyère. Ricotta can replace cottage cheese.
Make-Ahead: Assemble up to 24 hours in advance. Cover tightly and refrigerate. Let sit at room temperature for 20 minutes before baking. Add 5 extra minutes to baking time if needed.
Storage: Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat in microwave for 90 seconds to 2 minutes or in a 350°F oven.
Extra Crispy Top: Broil for the last 2 minutes of baking. Watch closely to prevent burning.
Protein Addition: Add diced cooked chicken, crumbled sausage, or cubed ham to make it a main dish.
Cheese Substitutions: Swiss cheese, Fontina, or aged white cheddar can substitute for Gruyère. Ricotta can replace cottage cheese.
Make-Ahead: Assemble up to 24 hours in advance. Cover tightly and refrigerate. Let sit at room temperature for 20 minutes before baking. Add 5 extra minutes to baking time if needed.
Storage: Store leftovers in an airtight container in the refrigerator for up to 4 days. Reheat in microwave for 90 seconds to 2 minutes or in a 350°F oven.
Extra Crispy Top: Broil for the last 2 minutes of baking. Watch closely to prevent burning.
Protein Addition: Add diced cooked chicken, crumbled sausage, or cubed ham to make it a main dish.