French🍚 Starches

Easy Potatoes au Gratin

Name: Easy Potatoes au Gratin
Total time: 1 h 30 min
Cuisine: French
Ingredients: 3 lb Potatoes; 1 Onion; ½ tsp Salt (for seasoning potatoes); ¼ tsp Black pepper (for seasoning potatoes); 60 g Gruyère cheese; 120 g Cheddar cheese; ½ cup Parmesan cheese; ¼ cups Unsalted butter; 2 cups Whole milk; 3 tbsp Flour; ¾ tsp Salt (for cheese sauce); ½ tsp Black pepper (for cheese sauce)

⏱ 90 min

A classic dish from the Dauphiné region of France, featuring thinly sliced potatoes layered with onions and smothered in a cheesy béchamel sauce, then baked until golden. A decadent, crowd-pleasing side dish perfect for gatherings and holidays.

Adapted from a video by Preppy Kitchen

Easy Potatoes au Gratin Recipe

Watch on YouTube

Ingredients

PotatoesPeeled and thinly sliced to about 1/8 inch thick; russet potatoes recommended3 lb
OnionLarge, halved and thinly sliced1
Salt (for seasoning potatoes)½ tsp
Black pepper (for seasoning potatoes)¼ tsp
Gruyère cheeseShredded, about 1/2 cup60 g
Cheddar cheeseShredded, about 1 cup; a flavorful white cheddar recommended120 g
Parmesan cheeseSprinkled on top for extra sharpness, optional½ cup
Unsalted butterAbout 56g, for the roux¼ cups

Steps

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1
Preheat oven to 350°F (175°C). Peel and rinse the potatoes, then thinly slice them to about 1/8 inch thick.
2
Halve the onion and cut it into thin slices.
3
Toss the sliced potatoes in a bowl with salt and black pepper to season.
4
In an 8x8-inch (or 2-3 quart) baking dish, shingle the potato slices, layering in onion slices between them, then tuck any remaining onion into gaps for flavor — don't worry about a perfect pattern.
5
In a medium pot over medium heat, melt the butter, then whisk in the flour and cook for about 2 minutes, whisking constantly, until it takes on a light color to form a roux.
6
Slowly drizzle in the warmed milk while whisking constantly to avoid lumps, and cook until the sauce bubbles and thickens slightly.
7
Remove the pot from heat and stir in the Gruyère and cheddar cheeses until melted, then mix in salt and black pepper.
8
Pour the cheese sauce evenly over the layered potatoes and onions, smoothing it out for full coverage; sprinkle Parmesan on top if desired for extra flavor.
9
Cover the dish with foil and bake at 350°F for 1 hour, then remove the foil and bake an additional 20-30 minutes until the top is golden.
10
Let it cool slightly before serving. You can assemble it a day ahead and refrigerate, or fully bake, cool, and refrigerate, then reheat by baking for 40 minutes with an extra splash of cream or milk on top to prevent drying out.

Easy Potatoes au Gratin

Ingredients

Steps

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