Preheat your oven to 375°F (190°C). Lightly grease a standard 12-cup muffin tin with butter or a bit of neutral oil, making sure to coat the sides and bottoms so the potatoes release easily after baking.
Peel the potatoes and slice them as thinly as you can, about 1/8 inch thick or thinner. A mandoline makes this quick and even, but a sharp knife and a bit of patience work just as well. Keep the slices in a bowl as you work.
Thin potato slices being cut on a kitchen board
Thin potato slices being cut on a kitchen board
In a small bowl or measuring cup, stir together the heavy cream, minced onion, salt, and black pepper. This seasoned cream is what gives the potatoes that classic, old-fashioned au gratin flavor with only a few ingredients.
Sprinkle about half of the shredded cheddar (1 cup) evenly into the bottoms of the 12 muffin cups, dividing it as evenly as you can. This cheese will melt and help form a browned, lacy edge around each potato cup.
Layer the potato slices into the muffin cups, fanning them slightly and pressing down as you go so each cup is filled just to the top. Try to distribute the potatoes evenly so all 12 cups bake at the same rate.
Potato slices layered into muffin cups before baking
Potato slices layered into muffin cups before baking
Give the cream mixture a quick stir, then carefully spoon it over the potatoes, dividing it evenly among all the cups. Pour slowly so the cream seeps down between the slices rather than overflowing onto the pan.
Top each cup with the remaining 1 cup of shredded cheddar, sprinkling it evenly over the surface. This final layer of cheese is what gives you that golden, bubbling, browned top like you’d see in an old bridge club buffet spread.
Place the muffin tin on a rimmed baking sheet to catch any drips. Bake on the middle rack for 35–45 minutes, or until the potatoes are tender when pierced with a knife and the tops are deeply golden and bubbling.
Muffin tin of au gratin cups baking on a sheet pan
Muffin tin of au gratin cups baking on a sheet pan
Remove the pan from the oven and let the potato cups rest in the muffin tin for at least 10 minutes. This short rest helps the cream set and makes it easier to lift them out in neat portions, just like my aunt did when she passed them around the card table.
Run a thin knife or offset spatula around the edges of each cup to loosen, then gently lift out the potato au gratin cups and transfer to a serving platter. Serve warm, and refrigerate any leftovers within 2 hours.
Potato au gratin cups arranged on a serving platter
Potato au gratin cups arranged on a serving platter
Variations & Tips
To keep this true to its 1958 bridge-club roots, the recipe uses just potatoes, cream, onion, and cheese, with salt and pepper for seasoning. That said, you can adjust within that framework. Swap the mild cheddar for Colby or a young Swiss for a slightly different but still period-appropriate flavor. If you prefer a milder onion note, grate the onion instead of mincing so it almost melts into the cream, or reduce the amount by half.
For a lighter version, you can use half-and-half instead of heavy cream, but the cups may weep a bit more liquid and won’t be quite as rich or set; bake them on the longer end of the time range. If you need to make them ahead, bake until just tender, cool, then reheat loosely covered with foil at 350°F until hot and bubbling.
Reheated potato au gratin cups beside brunch eggs
Reheated potato au gratin cups beside brunch eggs
For food safety, always refrigerate leftovers within 2 hours of baking, store them in a covered container, and reheat until steaming hot before serving again. Use caution when slicing potatoes with a mandoline—always use the guard—and be careful when removing the muffin tin from the oven, as the cream and cheese will be very hot and can bubble over.
Finally, if you grease the muffin tin well and let the cups rest before unmolding, they’ll release more easily and keep their shape on the platter.
