- Bring a large pot of lightly salted water to a boil.
- Cook pasta shells until tender but still slightly firm, about 10 minutes; drain and set aside.
- Heat oven to 375°F.
- Grease a 9x13-inch casserole dish.
- In a medium skillet on medium heat, melt margarine.
- Add shallot and stir until lightly browned, about 5 minutes.
- Whisk flour into margarine and shallots to form a smooth paste.
- Slowly whisk evaporated milk into flour mixture until it forms a smooth sauce; simmer until thickened, 2 to 4 minutes.
- Whisk cheddar cheese and mascarpone cheese into sauce until cheeses have melted, about 5 minutes.
- Stir pumpkin puree, lemon zest, salt, pepper, garlic powder, paprika, nutmeg, and hot sauce into the sauce until combined.
- Lightly mix in lobster tail meat, green peas, and cooked pasta shells until heated through, about 5 minutes.
- Pour pasta mixture into prepared casserole dish; top with panko crumbs and Parmesan cheese.
- Bake in oven until topping is brown and crisp, 40 minutes.
Serves 12.
Approximate Nutrient Analysis per serving (based on 1 pound lobster meat):
450 calories, 23 g fat, 11 g saturated fat, 85 mg cholesterol, 400 mg sodium, 36 g carbohydrate, 2 g fiber, 6 g sugar, 25 g protein
Approximate Nutrient Analysis per serving (based on meat from 1 pound lobster tail with shell):
430 calories, 23 g fat, 11 g saturated fat, 70 mg cholesterol, 350 mg sodium, 36 g carbohydrate, 2 g fiber, 6 g sugar, 20 g protein