Ultimate Baked Seafood Delight: Simply Irresistible

Melt 1/2 cup butter in a heavy skillet. Add onion and bell pepper; sauté until tender. Mix in 1/2 cup flour and cook over medium heat for 10 minutes, stirring frequently. Stir in crabmeat, remove from the heat, and set aside.

In a large Dutch oven, bring water to a boil. Add shrimp, scallops, and flounder; simmer for 3 minutes. Drain, reserving 1 cup cooking liquid. Set seafood aside.

Preheat the oven to 350 degrees F (175 degrees C). Lightly grease one 9×13-inch baking dish.

In a heavy saucepan, melt remaining 1/2 cup butter over low heat. Stir in remaining 1/2 cup flour; cook, stirring constantly, for 1 minute. Gradually add milk plus 1 cup reserved cooking liquid. Increase the heat to medium and cook, stirring constantly, until mixture is thickened and bubbly. Mix in Cheddar, vinegar, Worcestershire sauce, salt, pepper, and hot sauce. Stir in cooked seafood.

Press crabmeat mixture into the bottom of the prepared baking dish to form a crust. Spoon seafood mixture over crust and sprinkle with Parmesan.

Bake in the preheated oven for 30 minutes, or until lightly browned. Serve immediately.