Trim the grizzley valves on the inside (tough stringy stuff) and the hard fat on the outside. Stuff with bread stuffing like for chicken. Use skewers or string to hold closed. Brown in hot fat and then neslte in more stuffing if desired - but you don't get the world's best gravy if you do that. Add about 1 cup water or broth and bake covered about 4 hours at about 3ooş. Slive and serve with mache dpotatoes, veggies and gravy. Then the next day grind up the leftover heart and mix with hamburger for meatloaf or patties or just make hamburger gravy.
My kids didn't think much of heart but loved the stuffing and gravy - and the meal next day!
If you are going to eat part of an animal for food you have a responsibility to use as much of it as possible.