This oven baked 3-ingredients buttermilk baked potatoes recipe is one my grandmother passed down, and it’s the kind of simple side dish that quietly steals the show. It’s nothing fancy—just potatoes, buttermilk, and butter—but the way they bake together into crispy, golden skins and fluffy, creamy centers feels like a hug on a chilly March evening.

Rustic baked potatoes in a casserole dish on a kitchen table
Rustic baked potatoes in a casserole dish on a kitchen table

Around here in our little Midwestern town, this is the dish I pull out when the weather can’t decide between winter and spring, and everyone just wants something warm, comforting, and reliable on the table.

These buttermilk baked potatoes are lovely alongside roast chicken, meatloaf, baked ham, or simple pan-fried pork chops. I like to tuck the casserole into the oven while the main dish cooks so everything is ready at once. Add a bright green side like steamed green beans, roasted broccoli, or a simple salad with a tangy vinaigrette to balance the richness. For a cozy, all-in-one plate, spoon some of the buttermilk cream from the bottom of the dish over the potatoes and serve with crusty bread to soak up every last bit.

Family-style dinner plate with buttermilk potatoes and green beans
Family-style dinner plate with buttermilk potatoes and green beans

Oven Baked 3-Ingredients Buttermilk Baked Potatoes

Servings: 4–6

Ingredients

2 pounds small to medium russet or Yukon Gold potatoes, scrubbed and dried

2 cups full-fat buttermilk, well shaken
4 tablespoons unsalted butter, cut into small pieces
1 teaspoon kosher salt (optional, to taste)
1/2 teaspoon freshly ground black pepper (optional, to taste)

Potatoes, buttermilk, and butter arranged on a countertop
Potatoes, buttermilk, and butter arranged on a countertop

Directions

Preheat your oven to 375°F (190°C). Lightly butter or spray a 9x13-inch glass casserole dish so the potatoes don’t stick.

Scrub the potatoes well and pat them completely dry. Leave the skins on. If the potatoes are larger than a small fist, cut them in half lengthwise so they cook evenly and fit snugly in the dish.

Freshly scrubbed potatoes on a towel beside a cutting board
Freshly scrubbed potatoes on a towel beside a cutting board

Arrange the whole or halved potatoes in a single layer in the glass casserole dish, cut side down if halved. They should be nestled close together but not stacked.

Pour the buttermilk evenly over the potatoes. The buttermilk should come about halfway to three-quarters of the way up the sides of the potatoes, not completely covering them. Add a little more or less buttermilk if needed to reach that level.

Buttermilk being poured over potatoes in a baking dish
Buttermilk being poured over potatoes in a baking dish

Dot the tops of the potatoes with the small pieces of butter, spacing them so each potato gets a bit as it melts. If using, sprinkle the salt and pepper evenly over the potatoes and buttermilk.

Cover the dish tightly with foil and bake for 45–55 minutes, until the potatoes are just tender when pierced with a fork. The buttermilk will look slightly separated and thickened at this stage, which is exactly what you want.

Foil-covered casserole dish ready to go into the oven
Foil-covered casserole dish ready to go into the oven

Carefully remove the foil, gently spoon some of the thickened buttermilk over the tops of the potatoes, and return the uncovered dish to the oven. Bake for another 25–35 minutes, or until the tops and skins are golden brown and crisp and the centers are very soft and fluffy.

Once the potatoes are done, remove the dish from the oven and let it rest for about 5–10 minutes. The buttermilk will settle into a rich, spoonable cream around the potatoes. Serve the potatoes hot, spooning some of the creamy sauce from the bottom of the dish over each serving.

Golden baked potatoes with creamy sauce in the casserole dish
Golden baked potatoes with creamy sauce in the casserole dish

Variations & Tips

To keep this true to my grandmother’s 3-ingredient spirit, the base recipe sticks to potatoes, buttermilk, and butter, with salt and pepper as optional. Still, there are a few gentle tweaks you can make.

For extra-crispy skins, prick the potatoes a few times with a fork and rub them lightly with a bit of the butter before arranging them in the dish. If your family prefers a richer texture, swap 1/2 cup of the buttermilk for heavy cream while keeping the rest the same.

For kids or picky eaters, you can use peeled potatoes so everything is soft and creamy without the chew of the skin. If you need to make this ahead, assemble the dish up through adding the buttermilk and butter, cover, and refrigerate for up to 8 hours; add 5–10 minutes to the covered baking time.

Leftovers reheat beautifully: cover the dish with foil and warm in a 325°F (165°C) oven until heated through, or mash the leftover potatoes with the thickened buttermilk cream for an easy next-day mashed potato side.

Leftover baked potatoes mashed in a bowl with creamy sauce
Leftover baked potatoes mashed in a bowl with creamy sauce