If you are serving roast beef for Christmas dinner then it is almost inevitable potatoes will make an appearance too. We all know that beef and potatoes go together like salt and pepper but what if you add horseradish into the mix? Then the combination is a holy trinity of rich comfort food.

When it comes to potato gratins I’m a bit of a perfectionist. Nothing is worse than biting into a mouthful of gratin and discovering that the attractive looking bite is a gluey mess of cream and starch buried under bad cheese. {Shudder.} Luckily, this recipe avoids the pitfalls of bad gratins, producing a finished dish that will send potato lovers into a state of sheer bliss.

A good mandoline creates perfect potato slices of identical thickness. Simmered with cream, half and half, and garlic, the slices relax into pliable potato pieces, ready to be layered in the gratin dish. Fresh horseradish is stirred into the mix, adding a just touch of heat and a background kick that rescues the gratin from death by creaminess. Salty savory cheese is sprinkled on top of the layers of potatoes and then the entire dish can either wait a few days in the fridge or go straight into the oven. (The horseradish melds into the dish the longer it sits, and the flavor actually improves if the gratin is made a few days ahead of time.)

Once the gratin is cool enough to eat, your fork will cut through bubbly cheese into layer upon layer of tender potatoes. Creamy sweetness mingles with a subtle underlying heat achieving a level of taste bud nirvana that is nothing short of bliss.

Horseradish Potato Gratin (Printable Recipe)
Adapted from Epicurious
Serves 10

Note: The gratin can be prepared up until the point where you put it in the oven, up to 3 days in advance of cooking. Cover the assembled but uncooked gratin and keep it in the fridge until you are ready to bake.

Ingredients:

1 bunch fresh thyme
1 tablespoon black peppercorns
1 dried bay leaf
3 pounds boiling potatoes, such as Yukon Gold, peeled and cut crosswise into 1/8-inch slices
1 1/2 Tablespoons sea salt (note- sea salt is not table salt, if you do not have sea salt, substitute kosher salt)
5 garlic cloves, peeled and minced
2 cups heavy cream
2 cups half and half
1/4 cup fresh horseradish, grated (note- this is different than creamy prepared horseradish)
1 1/2 cups Parmesan (or Manchengo) cheese, coarsely grated

Directions:

Pre-heat the oven to 400°F with a rack in the middle position.

Generously butter a 2 1/2- to 3-quart gratin dish, other shallow baking dish, or 10 individual ramekins.

Make a bouquet garni by wrapping thyme, peppercorns, and a bay leaf in a 6-inch square of cheesecloth and tie it closed with string. (Or use a large tea ball.)

Set a heavy 6-quart saucepan over medium heat. Place the potatoes, bouquet garni, salt, garlic, cream, and half and half into the pan. Bring the liquid to a boil, then reduce the heat to low and maintain a simmer. Cook the potatoes, uncovered, until they can be pierced by a fork, about 10 minutes. Remove the bouquet garni and discard the contents. Stir the horseradish into the pan. Taste a potato slice and adjust the salt as necessary (keeping in mind that the cheese will bring additional saltiness to the dish).

Layer the potatoes into the buttered dish (or dishes), pouring any remaining liquid over the top. Sprinkle Parmesan cheese evenly on top of the potatoes. Set the dish in the oven and bake until the cheese is golden brown and the potatoes are tender, about 30-40 minutes. Let the gratin stand for 15 minutes before serving, to cool slightly.