Preheat the oven to broil and move the rack to the highest position. Line a baking sheet with aluminum foil or parchment.
Lightly butter each side of the slider buns. Sprinkle lightly with garlic salt.
Place the bottom only on the baking sheet, and place under the broiler to toast.
In a small mixing bowl, pour one cup of warm barbecue sauce over the warmed roasted chicken. Mix together until the sauce has evenly coated the chicken, and then set the bowl aside.
After the bottom buns have toasted, remove from the oven, and cover each with about 1/4 cup of barbecue chicken.
Place one half slice of cheese over the barbecue chicken.
Place the top buns on the baking sheet to the side. Return the pan to the oven, and broil until the cheese melts and the tops are toasted.
Remove the sliders from the oven.
To assemble, place a heaping tablespoon of cole slaw on top of the cheese then place the top on the slaw.
Skewer each slider with a toothpick and garnish with a dill pickle slice.