Gather the ingredients. Wash potatoes, remove imperfections.
Wash the beef heart. Use a sharp knife to remove arteries and fat. Slice into 1-inch cubes. Slice into large chunks potatoes and apples, remove the core. Peel onion, dice small.
In a large dutch oven over medium-high heat, melt ghee. Add meat and let it sit for 2-3 minutes without stirring so the sides can brown. Stir a couple of times to let meat brown from all sides but don't completely cook through. Add onions, stir well.
Add water to the pot. Add apples, potatoes, salt, and vinegar. Once water slightly started to boil, reduce the heat to low, cover, and simmer on low for 1 1/2 hours (or more). Serve warm; the best flavor will be the following day.
Notes
The trick to making beef heart taste good is to either cook it fast or slow. This recipe is simmering it, so the longer you can cook, the better.
Slice meat into larger cubes to make sure the meat is tender at the end.
Choose hard sweet apple variety.
Taste at the end to ensure a perfect balance between salt and acid; add more if something is missing.