Grass-fed Beef Liver, the nutritional powerhouse. Liver contains more nutrients gram for gram, than any other food. Contrary to popular belief, liver does not store toxins, and instead is responsible for neutralizing and eliminating them. It does however, store vitamins A, D, E, K, B12 and folic acid, and minerals such as copper and iron. (Check out this article by Chris Kresser).
If you aren't a fan of the taste of liver, try soaking it in milk or coconut milk for an hour before cooking.
Fry it, or grind and add to meatballs, meatloaf, burgers or chili.
[FRY] - Beef Liver with Fig, Bacon and Caramelized Onion Compote from The Healthy Foodie
[GRIND] - Rosemary Liver Burgers from Paleo Flourish
[PÂTÉ] - Beef Liver Pâté with Red Wine and Herbs from Nourishing Joy
Or, if you are't a fan of eating liver, try making your own grass-fed beef liver capsules!