Potato and Mushroom Gratin

Potato and Mushroom Gratin

You're gonna love this delicious Potato and Mushroom Gratin. Easy to assemble and results in a golden and creamy dish every single time. A no-fuss casserole loaded with earthy mushrooms and gruyère cheese, what's not to love?

Ingredients

2Tbsp
Salted Butterplus more for greasing dish
4 1/2cups
Cremini Mushrooms, thinly slicedor White Mushroom
3cloves
Garlic, minced
1cup
Heavy Cream
1cup
Sour Cream
1tsp
Kosher Salt
1/2tsp
Ground Black Pepper
1pinch
Ground Nutmeg
1/3cup
Milk
2Tbsp
All-Purpose Flour
2.5lb
Russet Potatoesor Red Potato
1 1/2cups
Gruyère Cheese, shredded
to taste
ChoppedFresh Parsleyor Sliced Scallionoptional
Nutrition Per Serving
Calories
411
Fat
25.2 g
Protein
12.9 g
Carbs
34.0 g

Cooking Instructions

step 1

Preheat oven to 375 degrees F (190 degrees C) and butter a large 3-quart casserole dish.

step 2

Melt Salted Butter (2 Tbsp) in a large skillet over medium-high heat until starting to foam. Add Cremini Mushrooms (4 1/2 cups) and cook until lightly browned and the moisture has evaporated.

step 3

Add Garlic (3 cloves) and continue to cook, stirring often for 1-2 minutes. Set aside.

step 4

While mushrooms are cooking, whisk together the Heavy Cream (1 cup), Sour Cream (1 cup), Kosher Salt (1 tsp), Ground Black Pepper (1/2 tsp), and Ground Nutmeg (1 pinch).

step 5

In a separate bowl whisk together the Milk (1/3 cup) and All-Purpose Flour (2 Tbsp) until smooth. Add to the sour cream and heavy cream and whisk until incorporated.

step 6

Peel and thinly slice Russet Potatoes (2.5 lb).

step 7

Spread half of the potato slices evenly on the bottom of the prepared casserole dish. Scatter half of the sauteed mushroom and half of the Gruyère Cheese (1 1/2 cups) evenly over the potatoes. Repeat with remaining potatoes, mushrooms, and cheese.

step 8

Pour the cream mixture evenly over the potatoes. Give the pan a gentle shake to help flatten everything out.

step 9

Cover and bake for 45-60 minutes (this will depend on how thin you've sliced the potatoes). Start checking at 45 minutes. The potatoes should be almost tender in the center.

step 10

Remove the cover and bake for an additional 20 minutes until the top is golden.

step 11

Remove from oven and allow to rest for 10 minutes before serving. Garnish with Fresh Parsley (to taste) if desired.