Ingredients:
- 2 tablespoons unsalted butter
- 2 tablespoons all-purpose flour
- 1 cup whole milk
- 1/2 cup grated Gruyère cheese (or Emmental)
- 1/4 teaspoon freshly grated nutmeg
- Salt to taste
- Black pepper to taste
Instructions:
- In a medium saucepan over medium heat, melt the butter until frothy, avoiding browning.
- Add the flour to the melted butter, whisking continuously for about 1 minute to form a roux; it should be pale and bubbly.
- Gradually whisk in the milk, stirring constantly to avoid lumps, until the mixture becomes smooth.
- Keep stirring until the sauce thickens and coats the back of a spoon (about 5-7 minutes).
- Remove from heat and stir in the grated cheese until fully melted and combined.
- Add nutmeg, salt, and pepper to taste. Adjust seasoning as necessary.
- Use immediately, or let cool and refrigerate for later use.