Mushroom Potato Gratin Courtesy Michelle Bernstein Martinez

Elevate your comfort food game with Michelle Bernstein Martinez's decadent Mushroom Potato Gratin. This indulgent side dish marries velvety layers of thinly sliced russet potatoes with savory cremini mushrooms, smothered in a luxurious blend of Gruyère and Parmesan cheeses. Infused with garlic, fresh thyme, and a rich cream sauce, it’s baked to golden, bubbling perfection. Perfect for holidays or special dinners, this gratin is both elegant and hearty, making it an unforgettable centerpiece on your table. Whether you're hosting a crowd or treating yourself, this Mushroom Potato Gratin promises layers of flavor in every bite.

Nutriscore Rating: 64/100

Prep Time:20 mins

Cook Time:60 mins

Total Time:80 mins

Servings: 6

Ingredients

• 4 large Russet potatoes
• 12 oz Cremini mushrooms
• 3 tbsp Unsalted butter
• 3 cloves Garlic
• 1.5 cups Heavy cream
• 1.5 cups Gruyère cheese
• 0.5 cups Parmesan cheese
• 1 tbsp Fresh thyme
• 1.5 tsp Salt
• 1 tsp Black pepper

Directions

Step 1

Preheat oven to 375°F (190°C) and grease a 9x13-inch baking dish with butter or nonstick spray.

Step 2

Peel the potatoes and slice them evenly into thin rounds, about 1/8 inch thick. Use a mandoline slicer if available for consistent slices.

Step 3

Clean the mushrooms with a damp cloth, remove stems, and thinly slice the caps.

Step 4

Melt 2 tablespoons of butter in a large skillet over medium heat, then add the mushrooms and cook for 6-8 minutes until they release their moisture and become golden. Season with 1/2 teaspoon of salt and 1/4 teaspoon of black pepper, then set aside.

Step 5

Mince the garlic and sauté it with the remaining 1 tablespoon of butter in a small saucepan over medium-low heat until fragrant, about 1 minute. Add heavy cream, thyme, 1 teaspoon of salt, and the remaining black pepper. Heat for 3-4 minutes but do not let it boil.

Step 6

In the prepared baking dish, layer one-third of the potato slices in an overlapping fashion. Top with half of the cooked mushrooms, 1/2 cup of Gruyère cheese, and 2 tablespoons of Parmesan cheese. Repeat the process for the second layer: potato slices, the remaining mushrooms, 1/2 cup of Gruyère, and 2 tablespoons of Parmesan.

Step 7

For the final layer, arrange the last one-third of the potato slices on top, then pour the cream mixture evenly over the entire dish. Sprinkle the remaining Gruyère cheese and Parmesan on top.

Step 8

Cover the dish tightly with aluminum foil and bake for 40 minutes. Remove the foil and bake for an additional 20 minutes, or until the top is golden and bubbling and the potatoes are tender when pierced with a knife.

Step 9

Remove the gratin from the oven and allow it to cool for 10 minutes before serving. Garnish with extra thyme, if desired.

Nutrition Facts

Serving size	(2212.0g)

Amount per serving	% Daily Value*
Calories	3780.5

Total Fat 235.5g	0%
Saturated Fat 139.6g	0%
Polyunsaturated Fat 3.4g
Cholesterol 715.3mg	0%
Sodium 5586.7mg	0%
Total Carbohydrate 281.5g	0%
Dietary Fiber 25.2g	0%
Total Sugars 21.5g
Protein 119.4g	0%

Vitamin D 71.3IU	0%
Calcium 2729.5mg	0%
Iron 16.9mg	0%
Potassium 8485.1mg	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: 56.9%

Protein: 12.8%

Carbs: 30.2%