Seafood Cakes with Creme Fraiche Dipping Sauce

Name: Seafood Cakes with Creme Fraiche Dipping Sauce
Ingredients: 2 tablespoons butter; 1/2 pound bay scallops; 1/2 pound 31 to 40 size shrimp, deveined and tails removed; 1 tablespoon chopped fresh flat leaf parsley leaves; 1/2 cup panko bread crumbs; 1 tablespoon garlic powder; 1 lemon, zest finely grated; 1 fresh mango, peeled, cut away from the pit and diced; 1/2 cup mayonnaise (or more as needed to bind patties); 1/4 cup Parmesan; Salt and freshly ground black pepper; 1 tablespoon olive oil, plus more as needed; 4 ounces creme fraiche; 4 ounces sour cream