Since everyone agrees that the best part of a macaroni and cheese is the crisp, crunchy topping, why not feature that as the star of the dish? This recipe makes extra cheese sauce, so save it in the fridge for the next batch.
Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally until cooked through but firm to the bite, 8 minutes. Drain.
Combine potato chip crumbs, Parmigiano-Reggiano cheese, bread crumbs, and butter in a skillet over medium heat; cook and stir until golden brown, about 5 minutes. Set aside.
Heat prepared white sauce, Cheddar cheese, Gruyere cheese, and dry mustard in a large saucepan over low heat; cook and stir until cheese melts, 3 to 4 minutes. Remove from heat.
Combine cooked macaroni with enough cheese sauce to make it as creamy as you like it (see Cook’s Note). Spoon mixture into 2 (10-ounce) ramekins or bowls and cover with toasted potato chip topping.
Per Serving: 2379 calories; protein 84.9g; carbohydrates 148.6g; fat 162.5g; cholesterol 243.6mg; sodium 3558.1mg.