Brown meat in a large skillet over medium heat. While the meat browns, mix the rest of the ingredients in a large mixing bowl to create the sloppy joe sauce.
When the meat is browned and drained, fold the sauce into the meat. The sauce needs to remain thick. But if you feel the sauce is too thick, add ¼ cup water to loosen it some.
Line a 9 x13 pan with the bottom halves of the slider buns.
Cover the bottom half of the buns with parmesan cheese and bake in your oven until the cheese is melted (about 5 minutes).
Take the buns from the oven, spoon the sloppy joe meat sauce evenly over the melted parmesan. Put the bun tops on and lightly brush with beaten egg whites. Sprinkle tops with Chia seeds.
Put bake in the oven for 5 minutes. The tops of your sliders will be a shiny golden brown.