Preheat your oven to 350°F.
Bring a large pot of salted water to a boil. Add the elbow macaroni and cook for 10 to 12 minutes, until the noodles are nice and tender but not falling apart. Drain well, return to the pot, and stir in 1 tablespoon butter to coat.
Combine the medium cheddar and white cheddar. Remove 1 cup of the cheddar mixture and set aside for topping.
Melt 4 tablespoons butter in a large skillet or pot over medium heat. Whisk in 4 tablespoons flour and cook for about 1 minute. Slowly whisk in the milk and half-and-half and cook, whisking often, until the sauce thickens enough to lightly coat the back of a spoon.
Reduce the heat to low. Add the American cheese and stir until completely melted and smooth. Add the remaining cheddar mixture, Parmesan, and Romano a little at a time, stirring until each addition melts before adding more.
Add pasta to the cheese sauce and stir to combine, adding salt and pepper, to taste.
Pour this mixture into a lightly greased 9x13 dish and sprinkle with the reserved 1 cup of cheese. Bake for 15 minutes, or until the cheese is melted, then broil for 1 to 2 minutes until the top is lightly browned and bubbly.
Let cool for 5 minutes, then serve warm.