Cheesy Mushroom Rice Casserole
A comforting casserole for the cozy holiday season.
Cheesy Mushroom Rice Casserole
Ingredients
- 6 tablespoons unsalted butter, divided
- 1 small onion, finely chopped
- 8 to 10 ounces mushrooms, cleaned and roughly chopped (cremini, baby bellas, porcini, and maitake work well)
- 3 tablespoons all-purpose flour
- 2 3/4 cups whole milk, room temperature
- 1 teaspoon dried thyme
- 3/4 teaspoon ground nutmeg
- 1/2 teaspoon dried sage
- 4 cups cooked white rice
- 1 3/4 cups grated white cheddar cheese, divided
- Kosher salt and freshly cracked black pepper, to taste
Preparation
- Preheat oven to 350°F and grease a 9x9 casserole dish with baking spray, set the casserole dish on top of a foil-lined baking sheet, and set aside.
- In a medium saucepan set over medium heat, melt 3 tablespoons butter and saute onions until soft and slightly translucent, about 8 to 10 minutes.
- Add mushrooms, cooking until they get some golden color on them, about 4 to 5 minutes.
- Add remaining 3 tablespoons butter to the pot. Once melted, whisk in flour, creating a base for a roux.
- Gradually add in milk, 1/2 cupful at a time, whisking constantly to prevent lumps. Once the sauce begins to thicken, add the next portion of milk.
- Once all of the milk is added, bring the sauce to a simmer and whisk in thyme, nutmeg, and sage. Season with salt and pepper.
- Turn the heat off and pour in the rice and 1 cup cheese, mixing to combine.
- Pour the mixture into the prepared pan and top with remaining 3/4 cup cheese.
- Bake until the sides start to bubble and the top is golden, about 25 to 30 minutes. Serve warm and enjoy!