Cut heart open and remove any veins and chambers inside. Soak in salt water overnight to remove any blood. Put it in a pot with enough water to cover by 1" add some salt , a bay leaf, a few peppercorns(whole) an onion quartered, and a few celery stalks with leaves . Bring to a boil then reduce heat to a simmer. Cook for about 2-3 hrs. remove heart. strain liquid . put liquid back into pot and add 1/2 cup water to which 2 tbs flour has been mixed in. increase heat while stirring in the flour mix until it thickens. slice heart and pour gravy on top. Serve with mashed potatoes and carrots. I usually cook the tounge at the same time. For the tounge remove and let cool , remove skin. refrigerate and slice like sandwitch meat when cold.