Preheat oven to 450 degrees °F. Melt butter and old bay seasoning together in the microwave. Cut lobster tail shells down the middle to expose the lobster meat. Brush each lobster with old bay butter mixture and add to an oven safe dish and cook for 10 minutes. Reduce oven temperature for 350 degrees °F.
Remove Lobster meat from the lobster shells and cut into chunks, brush with any additional butter and set aside.
Cook pasta according to package instructions. Drain noodles and set aside.
In a separate pan, melt butter over medium low heat. Add flour and stir together constantly for about 2 minutes, until thickened into a paste. Slowly add milk and whisk together constantly until smooth. Then add heavy cream. Cook together for about 3 minutes, until sauce begins to slightly thicken.
Add in old bay seasoning, smoked paprika, cayenne pepper, dried thyme, dried parsley, diced garlic, and salt to taste. Continue to whisk together, tasting as you go along. Whisk constantly for 3 minutes then remove from heat. Add in cheeses and fold together.
Add pasta to cheese sauce ensuring that all noodles are coated. Pour into a 9x13 baking dish. Add in sour cream and half of the lobster chunks and mix together with a spoon.
Top with additional cheese, breadcrumbs, and remaining lobster chunks. Bake for 35 minutes in the oven at 350 degrees °F. Then broil on the top oven rack for 3 minutes to give the macaroni and cheese a nice crust!
Remove from oven and allow macaroni and cheese to cool for about 10-20 minutes.