Flounder Stuffed With Shrimp and Crabmeat

1 tablespoon olive oil 2 tablespoons butter 1 small onion , chopped fine 2 garlic cloves , minced 2 stalks celery , chopped fine 1/2 red bell pepper , chopped[...]

1/2 small onion , minced 1 stalk celery , minced 1/4 red bell pepper , minced 1 garlic clove , minced 1/2 teaspoon Old Bay Seasoning 2 ounces lump crabmeat 2[...]