Preheat oven to 375 degrees.
In a large skillet over medium heat, melt butter. Add green bell pepper and onion, cook 5 minutes until softened. Remove from heat.
Combine onion/pepper mixture with breadcrumbs, crab, worcestershire sauce, dry mustard, old bay seasoning, salt, pepper and parsley.
Separate mixture evenly and place on center of flounder fillets.
Fold over ends of fillets and use toothpick to secure. Sprinkle witih paprika.
Cook for 25-30 minutes until fish begins to flake.
While fish is cooking, melt butter in saucepan over medium heat. Add shallot and garlic and cook for 3 minutes until fragrant.
Add wine, heavy cream and lemon juice. Cook for 5 minutes. Keep warm.
Drizzle sauce over fish for serving.