Ingredients
Scale
- 1 pound cremini mushrooms, sliced (you can substitute with button or shiitake mushrooms)
- 3 tablespoons unsalted butter
- 1 medium yellow onion, finely chopped
- 3 cloves garlic, minced
- 2 tablespoons all-purpose flour (gluten-free flour works well too)
- 1 ½ cups whole milk (or use almond milk for a lighter version)
- 1 cup heavy cream
- ½ cup grated Parmesan cheese
- 2 teaspoons fresh thyme leaves (or 1 teaspoon dried thyme)
- 1 teaspoon fresh rosemary, minced
- Salt and freshly ground black pepper, to taste
- 1 cup shredded Gruyère or mozzarella cheese for topping
- 1 cup panko breadcrumbs (optional, for added crunch)
- 2 tablespoons olive oil (for toasting breadcrumbs)
Instructions
- Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with butter or non-stick spray.
- In a large skillet, melt the butter over medium heat. Add the chopped onion and sauté until translucent and soft, about 5 minutes. This step always reminds me of Mama Lou’s gentle voice telling me to “take your time with the onions—they bring the base to life.”
- Add the sliced mushrooms to the skillet. Cook, stirring occasionally, until they release their moisture and start to brown, about 8-10 minutes. The smell at this stage is pure nostalgia—warm, earthy, and inviting.
- Stir in the minced garlic and cook for another minute until fragrant. Be careful not to burn it; I learned this the hard way, after a smoky kitchen mishap during a family gathering.
- Sprinkle the flour evenly over the mushroom mixture and stir well to coat. This will help thicken the sauce. Cook for 2 minutes, stirring constantly to avoid lumps.
- Gradually pour in the milk and heavy cream while stirring continuously. This is the moment the sauce begins to thicken beautifully, turning creamy and luscious.
- Reduce heat to low and stir in the Parmesan cheese, fresh thyme, and rosemary. Season generously with salt and pepper. Taste and adjust seasonings. I always remind myself here of Ouma’s advice: “Don’t rush the seasoning; flavors need time to tell their story.”
- Remove the skillet from heat and pour the mushroom herb sauce evenly into your prepared casserole dish.
- Sprinkle the shredded Gruyère or mozzarella cheese evenly over the top.
- In a small pan, heat olive oil over medium heat and toast the panko breadcrumbs until golden brown, about 3-4 minutes. Sprinkle the toasted breadcrumbs over the cheese layer for a delightful crunch.
- Bake uncovered for 25-30 minutes, until the top is bubbly and golden brown. The aroma that fills your kitchen will remind you of all those family dinners where warmth and laughter were the main ingredients.
- Let the casserole rest for 10 minutes before serving. This gives the sauce a chance to set and makes it easier to serve.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Main Dish
- Method: Cooking
- Cuisine: International
