Preparation Steps

• Finely shred the cheddar (a fine shred melts more smoothly). Set aside about 1 heaping cup for topping. Lightly grease a 3-quart/9x13-inch baking dish.
• Bring a large pot of well-salted water to a boil. Add the macaroni and cook until very firm—about 2 minutes shy of package al dente. Reserve 1/2 cup pasta water, then drain.
• While the pasta cooks, heat the oven to 375°F. In a wide saucepan over medium-low heat, warm the heavy cream with the dry mustard, smoked paprika, and 1/2 teaspoon of the kosher salt until steaming (do not boil).
• Remove the cream from the heat and whisk in the cream cheese until completely smooth and glossy.
• Return the pan to low heat and add about two-thirds of the shredded cheddar a handful at a time, stirring just until melted between additions. If the sauce seems too thick, loosen with 2 to 3 tablespoons reserved pasta water.
• Fold the drained macaroni into the sauce. Taste and add more salt if needed. Spread the mixture into the prepared baking dish.
• Scatter the remaining shredded cheddar evenly over the top. Bake on the center rack for 14 to 16 minutes, until the edges are bubbling and the center is hot.
• Switch the oven to broil and brown the top for 45 to 90 seconds, watching closely. Let the mac and cheese rest 8 to 10 minutes so the sauce sets and turns ultra-creamy before serving.