Season the chicken breasts with salt, pepper, garlic powder, and onion powder.
Add ½ cup of BBQ sauce as well as the chicken broth and Worcestershire sauce. Stir to combine.
Cover and cook on low for 4-5 hours or until the chicken is fully cooked and tender.
Once cooked, remove the chicken from the slow cooker and shred the chicken using two forks and mix it well with the remaining barbecue sauce. Keep warm.
Preheat the oven to 350 degrees.
Place the slider bottoms into a 9x13 baking dish. Add the shredded BBQ chicken over the slider bun bottoms.
Add the cheddar cheese in an even layer on top of the shredded chicken.
Place the pickles over the cheese, if using.
Next, top the sliders with the top of the buns.
Mix together the garlic powder and butter. Brush the mixture over the top of the slider buns.
Loosely cover the casserole dish with aluminum foil.
Bake for 12 to 15 minutes or until the cheese has melted. Serve immediately.