Homemade au gratin potatoes are a classic side dish! This beloved potato casserole is a welcoming sight on any dinner table or holiday spread. Our easy au gratin potatoes consist of layers of thinly sliced Yukon gold potatoes and yellow onions in a traditional creamy cheese sauce of Gruyere and cheddar cheeses.
Preheat the oven to 350 degrees. Lightly grease a 9x13 inch baking dish with cooking spray. Set aside.
Wash and dry the potatoes. Thinly cut the potatoes into 1/8-inch slices. Next, thinly slice the onions. Attractively arrange the sliced potatoes and onions in the prepared baking dish. Lay stacks of potatoes and onions upright on their sides until the baking dish is full.
In a large saucepan, melt the butter over low heat. Add flour, salt, and pepper. Stir until smooth. Gradually add the heavy cream to the flour mixture. Bring to a boil and cook, frequently stirring for about 2 minutes or until the sauce has thickened.
Remove the sauce from the heat and stir in both cheddar and Gruyere cheeses. Stir until melted. Next, pour the sauce over the potatoes and onions in the baking dish.
Cover the baking dish with tin foil — bake for 1 hour. After an hour, remove the tin foil and continue baking for an additional 30 minutes or until the potatoes are fork-tender and golden brown. Serve immediately. Enjoy!
When making au gratin potatoes, the all-purpose Yukon gold is a great choice. The Yukon gold does well to hold its shape, during baking. Learn more about the many types of potatoes.
Scalloped potatoes and au gratin potatoes are both widely popular potato casserole dishes. But the most significant difference between the two is cheese. Scalloped potatoes consist of thin layers of baked potatoes in a creamy sauce, usually covered with seasoned bread crumbs.
Similar to scalloped potatoes, au gratin potatoes also consist of thin layers of baked potatoes in a creamy sauce in addition to cheese, typically Gruyere.
For a classic version of homemade au gratin potatoes, prepare them in the oven. However, during the holidays, au gratin potatoes made in the crockpot is a fabulous alternative for busy home cooks.