White sauce is basically glorified melted cheese on your pizza dough. Whats not to like? It might seem intimidating to make a roux (thats the melted butter and flour combination that you add the milk to), but its actually pretty easy. When it starts to bubble all over, thats your cue to slowly drizzle in the milk. Have a whisk ready before you start cooking, because thats what keeps the sauce from clumping up.