Wash and rinse mushrooms, pat dry and slice leaving 4 whole ones for later. In a saucepan add butter or margarine. Add sliced mushrooms and jar of minced garlic. Saute till mushrooms are tender, set aside.
Place beef in a bowl, Add dry onion soup mix and mix together well. Add salt and pepper to desired taste.
Shape beef into 4 equal parts to make patties. Fry, grill, or broil burgers to your preference of doneness.
Place a generous helping of sauteed garlic and mushroom mixture on each burger. Place one slice of Swiss cheese on top of all and let the cheese melt. Toast Kaiser rolls. Place burger on roll and top roll with one garlic button and a whole mushroom secured with a toothpick.