Pre-heat oven to 350 degrees.
In a small bowl, mix together mayonnaise and BBQ sauce.
Slice slider rolls horizontally, keeping rolls connected, but separating tops from bottoms. Spread BBQ mayo on the top and bottom portion and place on foil-lined baking sheet.
Layer ham, turkey, and cheese on the bottom rolls. Top with sauerkraut, spreading to cover the meats and cheeses. Place slider tops over sauerkraut.
In a small bowl, mix melted butter and garlic powder together. Brush over the top of the sliders. Sprinkle black sesame seeds or poppy seeds on top.
Cover sliders with foil and bake for 10 minutes. Remove foil and bake for another 10 minutes, until cheese is melting and tops of sliders are golden.
Slice into 12 sliders and serve.