Lobster Macaroni and Cheese

1. Pour a bottle of beer into a large lobster pot. Bring to a boil, add the lobsters and steam the lobsters for 11 minutes. Then remove them from the pot and set aside to cool.
2. After cooling the steamed lobsters, crack them and remove the meat. Reserve the tails, and cut the remainder of the meat into large chunks.
3. Boil the pasta according to package instructions for al dente, then drain and set aside.
4. In a separate pan, over medium heat, melt the butter. Whisk in the all-purpose flour. Continue whisking for 1 minute until all lumps are removed and the flour has browned slightly. Stir in the milk and simmer for 10 minutes.
5. Separate the egg yolk from the white putting each into a separate bowl. Slightly beat the egg yolk with a fork. Add a small amount of the hot milk mixture (about 1 tablespoon) to the yolk and stir it together. This raises the temperature of the yolk (tempering). Stream the yolk mixture back into the milk mixture while continually stirring. Cook for 1 minute.
6. Over low heat, add the grated cheeses and stir until they are melted. Add the freshly grated nutmeg and dry (amontillado) sherry and stir to incorporate. Adjust with salt and pepper to taste. Set aside.
7. In a separate pan over medium heat, sauté the onion in a tablespoon of butter. Sauté until the onion is golden brown about 10 minutes. Set aside.
8. Preheat oven to 350 F. Start to layer the ingredients into an 8 ½ x 11 inch pan. Place half of the cooked noodles in the dish. Top with half of the cheese sauce.
9. Then add a layer of all the caramelized onions. On top of the onions, add all of the lobster meat that was cut into chunks (reserve the tails). Sprinkle on 2-3 tablespoons of grated Parmesan cheese.
10. On top of the grated cheese, add the remainder of the cooked noodles. Set aside 1/2 cup of the cheese sauce, placing the remaining sauce on top of the noodles. Sprinkle on 2-3 tablespoons of Parmesan cheese.
11. Bake uncovered for 20 minutes in a 350 F oven.
12. Remove the pan from the oven and place the lobster tails on top of the mixture. Drizzle the 1/2 cup of remaining cheese sauce on top of the lobster tails. Return the pan to the oven and bake for an additional 10 minutes.
13. This dish yields a generous 4 servings, each person receiving one lobster tail. If you want to stretch this dish to serve six to eight people, slice each lobster tail in half before placing it on top of the pasta.