Prepare chicken thighs by brushing each thigh with barbecue sauce, about 2 Tbsp per thigh, and season with salt and pepper, if desired.
Once your grill has been heated (roughly 450 degrees), cook chicken until it has been cooked through (165 degrees), about 5-6 minutes per side (if cooking inside on a grill top, cook chicken over med-high heat).
Pull chicken off of the grill, and allow to rest 3-4 minutes.
Shred chicken with two forks, then in a large bowl, mix chicken with cream cheese, sour cream, seasoned salt, remaining 2 Tbsp of barbecue sauce, and 3/4 cup of shredded cheese together. The heat from the chicken will help warm up all ingredients.
Once combined, spread dip in an oven-safe or grill-safe bowl. Top with remaining 1 and 1/4 cups of cheese. In the oven, broil on high for 3-4 minutes, or until cheese is golden brown and bubbly. If cooking on the grill, place dip inside the hot barbecue, covered, broiling for 3-4 minutes, or until cheese golden brown and bubbly.
Serve with tortilla chips, crackers, or bread. Top with extra barbecue sauce, green onions, or green chiles, if desired.
Enjoy!