Gather all your ingredients: unsalted butter, all-purpose flour, whole milk, salt, freshly ground black pepper, and nutmeg (if using).

In a medium saucepan over medium heat, melt the butter until bubbly, about 1-2 minutes.

Add the flour while whisking continuously for about 2 minutes until the mixture is smooth and bubbly.

Gradually pour in the milk while whisking constantly to prevent lumps. Continue whisking until the mixture thickens.

Remove from heat and season with salt, freshly ground black pepper, and nutmeg (if using). Stir well to combine.

Adjust the consistency by adding more milk if too thick, or return to heat and cook longer if too thin.

Your Velvety Béchamel Sauce is now ready to be used or stored.