Bring salted water to a boil and cook pasta until just al dente. Drain and rinse briefly to stop cooking. Set aside while preparing the sauce so it doesn’t overcook.
Melt butter in a skillet and gently cook lobster meat with seasoning for a few minutes. Cook just until opaque to keep it tender. Remove from heat and reserve.
Melt butter, whisk in flour to form a roux, then slowly add milk and cream. Once thickened, stir in cheeses and seasoning until smooth and creamy.
Return pasta to the pot and pour cheese sauce over it. Add cooked lobster and gently mix until every piece is coated in creamy sauce.
Transfer mixture to a greased baking dish and add extra cheese on top. Bake at 375°F until bubbly and golden, adjusting bake time depending on desired crust.