Layered Mashed Potato and Mushroom Casserole

Indulge in the comforting flavors of this Layered Mashed Potato and Mushroom Casserole, a hearty dish perfect for dinner gatherings or chilly evenings. Luxuriously creamy mashed potatoes form the base and topping, while a savory filling of sautéed cremini mushrooms, onions, garlic, and a touch of thyme takes center stage. Enhanced with a sprinkling of parmesan and a gooey mozzarella finish, this casserole strikes the perfect balance between rich, earthy flavors and cheesy decadence. It’s a crowd-pleasing vegetarian option that’s incredibly satisfying, simple to prepare, and gorgeous to serve. Whether enjoyed as a main course or a side, this casserole is sure to earn rave reviews at any table!

Nutriscore Rating: 71/100

Prep Time:25 mins

Cook Time:40 mins

Total Time:65 mins

Servings: 6

Ingredients

• 6 large russet potatoes
• 6 tablespoons unsalted butter
• 1 cup whole milk
• 2 teaspoons salt
• 0.5 teaspoons ground black pepper
• 2 tablespoons olive oil
• 1 medium onion
• 3 cloves garlic cloves
• 16 ounces cremini mushrooms
• 1 teaspoon thyme leaves
• 2 tablespoons all-purpose flour
• 1 cup vegetable broth
• 0.5 cup parmesan cheese, grated
• 1 cup mozzarella cheese, shredded
• 2 tablespoons parsley, chopped (optional for garnish)

Directions

Step 1

Peel and cut the potatoes into large chunks. Place them in a large pot, cover with cold water, and add 1 teaspoon of salt. Bring to a boil and let simmer for about 15-20 minutes or until fork-tender.

Step 2

While the potatoes are cooking, heat the olive oil in a large skillet over medium heat. Dice the onion and mince the garlic cloves, then sauté them in the skillet until softened, about 5 minutes.

Step 3

Slice the cremini mushrooms and add them to the skillet. Sprinkle with thyme leaves, and cook for 8-10 minutes, stirring occasionally, until most of the liquid from the mushrooms has evaporated.

Step 4

Sprinkle the flour over the mushroom mixture and stir to coat evenly. Pour in the vegetable broth and cook for another 2-3 minutes until the mixture thickens. Remove from heat and set aside.

Step 5

Drain the cooked potatoes and transfer them back to the pot. Add the butter and milk, then mash until smooth and creamy. Season with the remaining teaspoon of salt and the black pepper to taste.

Step 6

Preheat your oven to 375°F (190°C). Grease a 9x13-inch casserole dish lightly with oil or butter.

Step 7

Spread half of the mashed potatoes evenly in the bottom of the casserole dish. Spoon the mushroom mixture over the potato layer and spread it evenly. Sprinkle the parmesan cheese over the mushrooms.

Step 8

Top the mushroom layer with the remaining mashed potatoes, spreading it evenly to cover. Sprinkle the shredded mozzarella cheese over the top.

Step 9

Place the casserole dish in the preheated oven and bake for 25-30 minutes, or until the top is golden and bubbling.

Step 10

Remove from oven and let cool for 5-10 minutes. Garnish with chopped parsley before serving, if desired.

Nutrition Facts

Serving size	(3184.4g)

Amount per serving	% Daily Value*
Calories	3587.3

Total Fat 147.9g	0%
Saturated Fat 73.6g	0%
Polyunsaturated Fat 3.6g
Cholesterol 343.3mg	0%
Sodium 7048.5mg	0%
Total Carbohydrate 470.5g	0%
Dietary Fiber 41.7g	0%
Total Sugars 54.2g
Protein 120.4g	0%

Vitamin D 139.1IU	0%
Calcium 2003.6mg	0%
Iron 26.8mg	0%
Potassium 13324.0mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 36.0%

Protein: 13.0%

Carbs: 50.9%