In a medium bowl, mix together the hot sauce and 2 Tbsp of the dry ranch dressing mix.
Cut the chicken into eight, 2” chunks and toss in the hot sauce mixture. Cover the bowl with plastic wrap and refrigerate for at least an hour, or overnight.
Preheat the Indoor/Outdoor grill on setting 4.
Place the chicken on the preheated grill. Place the lid on the grill.
Grill the chicken for 6-8 minutes a side.
Meanwhile, in a small bowl, mix together the remaining dry ranch dressing mix, mayonnaise, sour cream and milk to create a dressing.
Top one bun with a chicken slider and a drizzle of ranch dressing. Serve warm.