Lobster Macaroni and Cheese

INGREDIENTS

Kosher salt

Vegetable oil

1 lb

elbow macaroni

1 qt

whole milk

1 stick

unsalted butter, divided

1/2 cup

all-purpose flour

12 oz

Gruyere cheese, grated (4 cups)

8 oz

extra-sharp Cheddar, grated (2 cups)

1/2 tsp

freshly ground black pepper

1/2 tsp

nutmeg

1 1/2 lb

cooked lobster meat

1 1/2 cups

fresh white bread crumbs (5 slices, crusts removed)