In college all I hunted was waterfowl mostly, just couldn't embrace the wonder that is an East River SD deer hunt! I try hard to cook waterfowl in ways that are not only tolerable, but (dare I say it) enjoyable too. My favorite for ducks, and this one really only works with birds taken later in the season, is similar to what 25Contender mentioned above. Mallards: pick the breast and filet the muscle skin-on up over the keel so that both pieces of meat are held in the center by skin. Marinate for at least 3 hours in 1 cup each apple cider (get the good stuff), chicken broth and brown sugar. Remove duck; marinade in large sauce pan and cook down to a glaze over medium heat. Grill duck breasts skin side down, basting with glaze as you turn it- DO NOT GO PAST MEDIUM!!! This recipe also uses a cajun mustard sauce on the side, the sweet/spicy combo is truly a remarkable pairing. I have a couple other go-to's, but this by far is my favorite. The trouble with waterfowl is as a general rule- it's very dark, and very rich meat. The best recipes I've found take time to put together…my snow goose gumbo is a 2 day process. Worth every minute, but who has hours to cook these days?
Cheers,
Plainsman