Ingredients

• 8 ounces (2 cups) elbow macaroni
• Kosher salt
• 3 tablespoons unsalted butter
• 3 tablespoons all-purpose flour
• 3 cups whole milk
• 3 cups coarsely grated American cheese, divided
• 3 tablespoons finely grated Parmesan
• 1 1/4 teaspoons freshly ground black pepper
• 1 1/4 teaspoons mustard powder
• 1/8 teaspoon paprika

Instructions

1. Preheat oven to 350°F. Cook macaroni in a large pot of boiling salted water, stirring occasionally, until noodles are very tender. Drain; transfer to a 3-quart baking dish.
2. Meanwhile, melt butter in a medium pot over medium heat. Whisk in flour and cook, whisking, until pale golden, about 2 minutes. Whisking vigorously and constantly, gradually add milk. Bring to a simmer. Reduce heat to low; add 2 1/2 cups American cheese and whisk until melted. Whisk in Parmesan, pepper, and mustard powder. Season with salt.
3. Pour cheese sauce over noodles in dish; stir to coat. Sprinkle remaining 1/2 cup American cheese over. Sprinkle with paprika. Bake until cheese is browned on top and bubbling around edges, 40-45 minutes.