Onion Potato Gratin Recipe

Name: Onion Potato Gratin
Prep time: 20 min
Cook time: 80 min
Total time: 100 min
Yield: Serves 1 or more
Ingredients: 2 pounds of thinly sliced potatoes; Onion; Salt & Pepper; 2 cups of half-and-half; Cooking Spray; Swiss Cheese; 2 tablespoons of butter

This comforting and flavorful onion and potato gratin is the perfect side dish to elevate your next roast, meatloaf, or even grilled chicken. Thinly sliced potatoes and onions are layered with creamy cheese, then baked to golden perfection in a rich half-and-half sauce. Get ready for a side dish that will steal the show!

Prep Time 20 mins

Cook Time 80 mins

Calories 403.3 kcal

Protein 32g

Rating 4.7 (6 Reviews)

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Recipe adapted from Food.com. Standardized by Forktionary.

Ingredients for Onion Potato Gratin

2 pounds of thinly sliced potatoes
Onion
Salt & Pepper
2 cups of half-and-half
Cooking Spray
Swiss Cheese
2 tablespoons of butter

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How to Make Onion Potato Gratin

Preheat oven to 425°F (220°C).
Spray a 9x13 inch oval baking dish with cooking spray.
Thinly slice 2 pounds of potatoes and 2 large onions.
Layer half of the potatoes in the prepared baking dish. Top with half of the onions and 1 cup of shredded Gruyère cheese.
Season with salt and pepper.
Repeat layers with remaining potatoes, onions, and cheese.
In a bowl, whisk together 2 cups of half-and-half and 1/4 teaspoon of salt.
Pour half-and-half mixture evenly over the top layer of potatoes.
Dot the top with 2 tablespoons of butter, cut into small pieces.
Cover the baking dish with foil.
Bake for 45 minutes.
Remove foil and bake for an additional 15 minutes, or until the potatoes are tender and the top is golden brown.