Preheat the grill.
In a medium bowl, gently mix together the beef, 2 tablespoons stout and onion powder. Make sure that you only mix as little as necessary, over working the meat will make it tough. Form into 6 patties (make sure to form patties larger than you want the final results to be, patties shrink as they cook).
Brush patties on both sides with butter, sprinkle liberally with salt and pepper.
Grill on both sides until medium, about 4 minutes per side.
Fill the buns with patties, jalapenos, bacon and cheese sauce.