Cut the heart in half and prepare it by cutting off any white fat on the surface as well as any arteries inside of it.
3 lbs beef heart
Heat a pot or saucepan over a medium heat and fry the onion with the heart in some cooking fat until browned on all sides.
1 onion, Cooking fat
Pour in the stock, paprika, bay leaf, cayenne pepper and season to taste with sea salt and freshly ground black pepper.
2 cups beef stock, 1 tablespoon paprika, 1 bay leaf, A pinch of cayenne pepper, Sea salt and freshly ground black pepper to taste
Bring to a simmer and simmer, covered, for 1 hour.
Add the vegetables except the tomatoes and simmer for another 15 minutes.
2 carrots, 1 leek, 2 celery stalks, 1 celeriac
Add the tomatoes and simmer for another 10 minutes.
1 can
Discard the bay leaf and serve.