Grown Up Mac and Cheese

INGREDIENTS

• 4 ounces thick-sliced bacon
• Vegetable oil
• Kosher salt
• 2 cups elbow macaroni or cavatappi (I used gemelli)
• 1½ cups milk
• 2 tablespoons unsalted butter
• 2 tablespoons all-purpose flour
• 4 ounces Gruyere cheese, grated
• 3 ounces extra-sharp Cheddar, grated
• 2 ounces blue cheese, such as Roquefort, crumbled
• 1/4 teaspoon freshly ground black pepper
• Pinch nutmeg
• 2 slices white sandwich bread, crusts removed
• 2 tablespoons freshly chopped basil leaves