01 - Preheat the grill to medium heat.
02 - Grill the Leberkäse slices for about 4-5 minutes on each side until they are nicely browned and heated through.
03 - During the last minute of grilling, place a slice of cheese on each piece of Leberkäse to melt slightly.
04 - Toast the slider buns on the grill for about 1-2 minutes until golden.
05 - Spread mustard on the bottom bun, add a piece of grilled Leberkäse with melted cheese, top with lettuce and tomato, and finish with the top bun.
06 - Serve immediately while hot.