This oven baked 4-ingredient potato gratinee is the kind of old-fashioned side dish that earns a permanent spot in the family recipe box. With tender potato slices, a rich creamy base, and a golden cheesy top, it feels special enough for holidays but simple enough for a weeknight dinner. Recipes like this became popular in mid-century home kitchens because they relied on a handful of practical ingredients and turned them into something comforting, hearty, and company-worthy.

Serve this potato gratinee alongside baked ham, roast chicken, meatloaf, pork chops, or a simple steak. It also pairs nicely with green beans, a crisp side salad, steamed broccoli, or glazed carrots to balance the richness. If you're putting together a brunch spread, it works beautifully next to eggs and fruit as well.

Oven Baked 4-Ingredient Potato Gratinee

Servings: 6

Bubbly golden potato gratin in a vintage green baking dish
Bubbly golden potato gratin in a vintage green baking dish

Ingredients

2 pounds russet potatoes, peeled and thinly sliced

1 can (10.5 ounces) condensed cream of mushroom soup
1 cup sour cream
2 cups shredded cheddar cheese, divided

Directions

1. Preheat the oven to 350°F and lightly grease a 2-quart baking dish.

2. In a medium bowl, stir together the condensed cream of mushroom soup, sour cream, and 1 1/2 cups of the shredded cheddar cheese until well combined.

3. Layer half of the sliced potatoes in the prepared baking dish, spread half of the cream mixture over them, then repeat with the remaining potatoes and cream mixture.

4. Sprinkle the remaining 1/2 cup cheddar cheese evenly over the top, cover with foil, and bake for 45 minutes. Remove the foil and bake for 20 to 25 minutes more, until the potatoes are tender and the top is bubbly and golden brown.

5. Let the gratinee rest for 10 minutes before serving so the layers can settle and the sauce thickens slightly.

Variations & Tips

Extra cheesy: If your family likes a thicker cheesy crust, increase the cheddar to 2 1/2 cups and add the extra cheese right on top during the last 20 minutes of baking.

Make-ahead tip: Assemble the dish up to a day ahead, cover, and refrigerate. Let it sit at room temperature for about 20 minutes before baking, and add a few extra minutes to the covered baking time if it is still quite cold.

Soup swap: Cream of chicken or cream of celery soup can be used instead of cream of mushroom if that's what you have in the pantry. Each one gives the casserole a slightly different flavor while keeping the same creamy texture.

Potato prep: Slice the potatoes as evenly as possible so they cook at the same rate. A mandoline is helpful for this if you have one, but a sharp knife works just fine for a cozy homemade result.