2 Tbsp Butter
2 Tbsp Flour
1-2 cloves garlic, finely minced
2 cups heavy cream (or whole milk)
6-8 oz Parmesan cheese, finely shredded
Salt & White pepper to taste
Melt butter in pan over medium/low heat. Add garlic. Add flour & whisk constantly for a minute or two (to cook out the flour taste). Slowly pour in cream while whisking, allowing to thicken before adding more. Melt in cheese & season with salt & pepper to taste. Reduce over medium heat, stirring constantly, until you reach your desired consistency.
(Sometimes I use 3 Tbsp of Butter, or else go a little shy on the flour. When I add too much flour it doesn't really dissolve and my sauce has a gritty texture.)