Prepare beef heart by trimming fat, and dicing into one inch cubes. How much time you want to take to devein is up to you. I find that once the meat is cooked, the veins are pretty much indistinguishable, so I don’t like waste much time on this part.
Toss into slow cooker, and sprinkle with pepper, salt, garlic powder, and oregano. Stir to coat beef cubes.
Top with slices onions.
Cook on high for 4-6 hours.
Serve over steamed rice, or quinoa, or for a more low carb dish, riced cauliflower.