Potatoes Mary Margaret

These are scalloped potatoes with one smart twist: the cream, butter, and garlic get simmered and reduced by half before they ever touch the potatoes. That pre-reduction concentrates the garlic flavor and thickens the cream so it coats each potato slice in a rich, clingy sauce instead of just pooling at the bottom of the dish.

Red-skinned potatoes hold their shape better than russets during the long bake. Sliced very thin (a mandoline helps enormously here), they cook through evenly and create those beautiful layered edges that crisp up around the sides of the casserole.

Parmesan layered between the potato slices melts into the cream and creates pockets of salty, nutty flavor throughout. A dusting of paprika on top before baking gives the gratin a warm golden color.

An hour and a half in the oven sounds long, but thin-sliced potatoes submerged in reduced cream need that time to fully absorb the liquid and turn tender all the way through.

Chef Tips

• Slice the potatoes uniformly thin. Thick slices stay crunchy in the center even after 90 minutes.
• Reduce the cream at a gentle simmer, not a boil. Boiling cream can break and turn grainy.
• Butter the casserole dish generously. The edges of the gratin are the best part, and stuck-on potato edges are a tragedy.
• Let the gratin rest 10 minutes after baking. The sauce thickens as it cools and the layers hold together when you serve.

Variations

• Add a layer of thinly sliced onions between the potato layers for extra sweetness.
• Use Gruyère instead of Parmesan for a more traditional French gratin dauphinois approach.
• Stir a teaspoon of fresh thyme into the cream while it reduces for an herbal note.