Ingredients

• 3 tablespoons (40 grams) unsalted butter

• 3 tablespoons (25 grams) all-purpose flour

• 1 cup heavy cream

• 1 cup water

• Kosher salt and white pepper, to taste

• freshly grated nutmeg, to taste

• 4 to 6 ounces grated Gruyère, Comté, or Fontina cheese

Instructions

Prepare the Roux

Melt the butter in a heavy-bottomed saucepan over medium heat, making sure not to let it brown. Add the flour while whisking to create a smooth paste. Cook, stirring frequently, for 2 to 4 minutes to remove the raw flour flavor.

Prepare the Cream Mixture

While the roux is cooking, combine the heavy cream and water in a separate container and stir to combine.

Combine the Roux and Cream

Once the roux has cooked, gradually add the cream mixture, about 1 tablespoon at a time, whisking continuously. The mixture will initially be very thick but will thin as more liquid is added. Continue adding the cream mixture until fully incorporated.

Simmer the Sauce

Reduce the heat and allow the sauce to simmer gently for approximately 10 minutes.

Season and Add the Cheese

Season to taste with Kosher salt, white pepper, and freshly grated nutmeg. Stir in the grated cheese using a heatproof spatula or spoon.

Keep Warm and Serve

Keep the heat very low once the cheese has been added. Place a piece of parchment paper (a cartouche) directly on the surface of the sauce to prevent a skin from forming.