I grind my burger pure after spending some amount of time making sure there are no glands blood or fat in the meat. Then vacuum pack and freeze in pound packages. If I want to add anything to it I do so at cooking time which for me consists of salt, pepper. Minced onion and a bit of sugar. 1/3 tsp?. Then I form the patties and coat them in melted bacon grease. After that I set them aside and get the grill hot, cleaned and oiled. When I cook them I want them just done or they become dry. It’s not easy but f you nail it they are mouth watering... Some like there’s pink but for me the flavor is better when just done.