In a large skillet, spray with cooking spray and add the cooked duck, southwestern style corn, black beans, and taco seasoning. Add 1/2 cup water and cook on medium low heat until heated through.
In another pan heat your refried beans on medium low until warm and shut off stove, set aside.
Once your meat mixture is ready, spray a large cast iron skillet with cooking spray, lay one shell down, spread with refried beans, top with some of the meat mixture, add your cheese, and top with another shell. Continue until the meat mixture and refried beans are all used up.
Top with the rest of your cheese and bake in an 350° oven for 30 minutes. I also used Mrs. Dash's Southwestern Chipotle Seasoning and I sprinkled it all over the top of the cheese. Serve with sour cream and salsa, optional.