Convert temperatures to C in the following recipe, please. Place the patties on the hot grill or griddle and cook for about 3-4 minutes per side for medium-rare, or longer if you prefer your burgers more well-done. If using a grill, use the spatula or tongs to gently press down on the patties to help them cook evenly. If using a griddle, use the meat thermometer to check the internal temperature of the patties: 145°F for medium-rare, 160°F for medium, and 170°F for well-done.