Preheat the oven to 375°F (190°C). Line a half sheet pan with aluminum foil and coat with nonstick cooking spray.
Pat the chicken pieces dry with paper towels to remove excess moisture, then arrange them skin side up on the prepared pan.
Sprinkle seasoning salt evenly over both sides of the drumsticks and thighs, using about 1 tablespoon total for all 8 pieces or to taste.
Spoon or brush about 3/4 cup BBQ sauce over the chicken pieces so they are coated evenly.
Bake in the preheated oven for 35–45 minutes, or until an instant-read thermometer inserted into the thickest part reads 165°F (74°C).
About halfway through baking, optionally brush the chicken with additional BBQ sauce for extra glaze.
Remove the chicken from the oven and tent loosely with foil; let rest for 10 minutes before serving. Sprinkle with chopped fresh parsley if desired.