Instructions

1. Preheat the oven to 350° F and spray a casserole dish (approximately 4 1/2 quarts) with non-stick cooking spray.
2. Bring a large pot of salted water to a boil. Add the cavatappi and cook according to the package directions until al dente. Reserve 1/4 cup of the starchy cooking water, drain the pasta and set aside.
3. In a deep, wide saucepan over high heat, add the lobster shells, sherry, water, and garlic. Squeeze the lemon into the stock, place it in the pan, and cover with a lid. Bring to a boil, reduce the heat to medium, and simmer until the stock is reduced by about 1/2, about 10 minutes.
4. Strain the lobster stock, set aside, and reduce the pan’s heat to low.
5. Mince the shallot and chop the thyme and parsley.
6. Add the butter to the saucepan. Once it begins to foam and sizzle, add the shallots and a pinch each of salt and pepper and sauté until fragrant, about 45 seconds. Add the flour and cook, whisking often until the roux is a light golden color, for 2 minutes.
7. Still whisking, pour in the lobster stock and the milk and turn the heat to medium. Cook, continuing to whisk often until the sauce is thickened and smooth. Turn off the heat and whisk in the salt, pepper, and nutmeg.
8. Stir in the mascarpone, fontina, cheddar, 1/4 cup of the parmesan, and the thyme until the cheeses are fully incorporated into the sauce.
9. Fold in the chopped lobster meat, cooked pasta, and reserved pasta cooking water to the cream sauce, and stir well to combine. Pour the mixture into the greased casserole dish and sprinkle with the breadcrumbs, remaining parmesan, and paprika.
10. Bake until the top is lightly golden, about 25-30 minutes, and then broil until bubbly, about 1 minute, keeping an eye on the dish as the top browns quickly. Allow the mac and cheese to rest for several minutes, garnish with the parsley, and serve.