Preheat oven to 400°F.
Prepare macaroni as indicated on the package instructions. Drain them 2 minutes before the time indicated on the package. Rinse the pasta under the cold running water.
Melt 3 tablespoons of butter and place it in a small mixing bowl. Let it cool and set aside.
Melt 4 tablespoons of butter in a skillet or a saucepan.
Add onion and garlic, and cook until translucent.
Add in flour and stir for approximately one minute.
Pour in the milk and whisk vigorously until lump-free.
Cook over low heat until it begins to thicken.
Season with salt, pepper, and nutmeg.
Stir in lobster, shrimp tails, pasta and grated cheese.
Add breadcrumbs in a mixing bowl with previously melted butter. Season with Italian seasoning, smoked paprika, onion powder, garlic powder, cayenne pepper, and salt.
Top the pasta with the mixture and bake for 20 minutes.
Remove from the oven and let it cool for a couple of minutes.
Serve and enjoy!