INGREDIENTS
1 lb
elbow macaroni
Kosher salt
1 qt
whole milk
1 stick
unsalted butter, divided
1/2 cup
all-purpose flour
8 oz
Gruyere cheese, grated (2 cups) OR pecorino Romano
8 oz
extra-sharp cheddar, grated (2 cups)
1/2 tsp
freshly ground black pepper
1/2 tsp
dry mustard
1/8 tsp
smoked paprika
6
slices white bread, crusts removed