Lobster Mac & Cheese with Mascarpone

1. In large saucepan, bring water to a boil. Cook macaroni according to package directions; drain. Transfer macaroni to large bowl and combine with mascarpone and Romano cheese until well coated.
2. In medium saucepan, heat 3 tbsp. butter; add lobster and saute until heated through. Remove from heat and stir in milk, green onions, salt, cayenne and nutmeg. Combine lobster mixture with macaroni mixture in bowl; transfer to well-greased 2-quart baking dish.
3. In small bowl, combine cream, egg and sherry; whisk to blend. Pour over macaroni mixture in baking dish. In small mixing bowl, combine bread crumbs and remaining 2 tablespoons butter; mix to combine. Spread bread crumbs over macaroni mixture.
4. Preheat oven to 350 F. Bake macaroni 25 to 35 minutes or until browned. Serve immediately.