01 - Preheat the oven to 400°F. Grease a 2-quart baking dish with butter or cooking spray.
02 - Bring a large pot of salted water to a boil. Cook the elbow macaroni until just al dente according to package directions. Drain well and set aside.
03 - In a large saucepan over medium heat, melt 3 tbsp butter. Whisk in the flour and cook, stirring constantly, for 1 minute to form a roux.
04 - Gradually whisk in the whole milk, stirring continuously to prevent lumps. Cook for 4–5 minutes, stirring frequently, until the sauce slightly thickens and coats the back of a spoon.
05 - Remove the saucepan from heat. Stir in the sharp cheddar, Gruyère, and Parmesan cheeses until completely melted and smooth. Add the Dijon mustard, smoked paprika, salt, and black pepper to taste.
06 - Gently fold the cooked macaroni and chopped lobster meat into the cheese sauce until evenly distributed.
07 - Pour the lobster macaroni mixture into the prepared baking dish, spreading it evenly.
08 - In a small bowl, combine the fresh breadcrumbs, melted butter, and finely chopped parsley. Mix until the breadcrumbs are evenly coated.
09 - Sprinkle the breadcrumb mixture evenly over the mac and cheese. Bake for 20–25 minutes until the top is golden brown and the sauce is bubbling around the edges.
10 - Remove from the oven and let the dish rest for 5 minutes before serving to allow the sauce to set slightly.