Melt 2 tablespoons butter in a saucepan over medium heat
Whisk in 2 tablespoons all-purpose flour
Cook for 1 to 2 minutes
Slowly whisk in 1 cup milk or cream
Continue whisking until smooth
Cook until the sauce thickens
Add salt to taste
Add black pepper to taste
Add garlic, cheese, or herbs if desired
Remove from heat and serve immediately