Creamy Classic Mornay Sauce Recipe: Velvety and Nutty

Melt the butter in a heavy-bottomed saucepan over medium heat until it foams.

Stir in the flour and whisk constantly for 1-2 minutes until the roux reaches a blonde color and smells slightly nutty.

Slowly pour in the milk a splash at a time, whisking vigorously after each addition to prevent lumps.

Bring the mixture to a gentle simmer, stirring constantly until the sauce thickens enough to coat the back of a spoon.

Stir in the salt, pepper, and ground nutmeg.

Remove the pan from the heat to ensure the cheese does not separate.

Add the grated Gruyère and Parmesan in handfuls, stirring gently until the sauce is glossy and the cheese is fully melted.