Preheat the oven to 400 degrees F.
Season the butter with salt and cayenne pepper and freeze the butter for 30 minutes. In a small bowl, combine the onions, peppers, garlic, sport peppers, and pickle juice together. Season the mixture with salt and cayenne pepper.
Place a large towel on a cutting board. Place the turkey directly on top of the cloth. This will prevent the turkey from sliding. Remove the neck, gizzards and livers from the cavity of the turkey. Rinse the turkey under cool water and pat dry with paper towels. Place the turkey, breast side up, on the work surface with the cavity facing you. Using a sharp knife, make three slits on either side of the breast bone, without breaking through the skin. Insert 2 to 3 slices of the frozen butter into each slit. Season each slit with salt and cayenne pepper. Insert about a teaspoon of the vegetable mixture into each slit, pushing with your fingers. Carefully stuff the boudin sausage in-between the flesh and skin. Gently pull the drumstick forward and outward to expose the inner thigh Pull the skin away from the meat. Make a slit following the bone line from the top of each leg. Using your index finger, make a path and stuff with the butter and vegetables. Season the skin which has been loosened around the inner thigh with salt and cayenne pepper. Turn the turkey breast side up, with the neck opening facing you. Lift the skin flap and make a slit down each wing from the shoulder, again following the bone lines. Stuff each wing with butter and vegetables. Season the outside of the turkey with salt and cayenne pepper. Stuff the cavity with any leftover boudin sausage, butter and vegetables. Secure the wings by folding the lower half back over the top of the wing. Tie the legs together with kitchen twine Place the turkey in a large deep roasting pan.
Roast the turkey for 15 to 20 minutes. Lower the heat to 350 degrees F. Cover the turkey with a lid and bake for about 3 to 3 1/2 hours, or until the juices run clear. Remove from the pan and let cool for 10 minutes. Lift the turkey our of the pan and carve. Serve with the pan juices.