I made elk burgers not to long ago and used about 2lbs of ground meat. When forming your patties, I grate about a 1/2 stick of butter evenly over all the patties. This adds a little fat to your lean elk. Then I finish them off with salt, pepper and a little garlic salt and threw them onto a hot grill to get a nice sear on one side, then flip turn down to half heat and let it cook thoroughly and add your cheese to the seared side and allow it to melt. I also threw some bacon on the top grate of the grill and served it on top. Toast your buns with a little butter in a pan and add whatever toppings you like. Some darn good burgers with a simple recipe.