I don't recommend deer fat... it has a really bad after taste. I prefer to wrap a tenderloin or small steak in bacon and cook it on the grill with some Garlic and Season-All. Now that is living! I don't like liver of any kind ... at all. But I do really like the heart cooked many different ways. I've even had it pickled. Stir fried with onions and gravy over toast is very good also.
FYI-in MI we cannot legally bone-out the deer in the field and leave the remains. Proof of sex must remain until the deer has been fully processed.