Ingredients:
One 16-ounce box elbow macaroni
2 tablespoons olive oil
4 ounces lightly smoked slab bacon, cut into 1/4-inch dice
5 cups whole milk
1/2 stick unsalted butter
1/2 cup all-purpose flour
1 cup grated Parmesan cheese
3 cups grated Gruyère cheese
1 1/2 teaspoons salt
1/2 teaspoon freshly ground white pepper