Description
Indulge in the rich and comforting flavors of this French Onion Mushroom Casserole. Caramelized onions, savory mushrooms, and a creamy cheese sauce come together to create a delicious side dish that’s perfect for any occasion.
Ingredients
Scale
For the Onion-Mushroom Mixture:
- 2 tablespoons unsalted butter
- 1 tablespoon olive oil
- 2 large yellow onions, thinly sliced
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- 1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried thyme)
- 16 ounces cremini or white mushrooms, sliced
- 2 garlic cloves, minced
- 1 tablespoon all-purpose flour
- 1/2 cup dry white wine (or vegetable broth)
- 1/2 cup beef or vegetable broth
- 1/2 cup sour cream
For the Topping:
- 1 cup shredded Gruyère cheese (or Swiss cheese)
- 1/2 cup grated Parmesan cheese
- 1 cup crushed buttery crackers (like Ritz)
- Optional: fresh parsley for garnish
Instructions
- Preheat the oven: Preheat the oven to 375°F and lightly grease a 9×9-inch baking dish.
- Caramelize the onions: In a large skillet, cook onions with salt and pepper until caramelized.
- Add mushrooms: Add mushrooms, thyme, and garlic; cook until mushrooms are tender.
- Make the sauce: Sprinkle flour, pour in wine and broth, then stir in sour cream, Gruyère, and Parmesan.
- Assemble and bake: Transfer mixture to baking dish, top with cheeses and crackers, then bake until golden and bubbly.
- Garnish and serve: Garnish with parsley if desired before serving.
Notes
- To make this dish vegetarian, use vegetable broth and wine instead of beef broth.
- This casserole pairs well with roasted meats or as a standalone vegetarian main.
Nutrition
- Serving Size: 1 scoop
- Calories: 310
- Sugar: 5g
- Sodium: 420mg
- Fat: 21g
- Saturated Fat: 11g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 19g
- Fiber: 2g
- Protein: 10g
- Cholesterol: 45mg
