Sticky Barbecue Chicken

Name: Sticky Barbecue Chicken
Cuisine: American
Ingredients: ¼ cup smoked paprika; 2 Tbsp. light brown sugar; 2 tsp. chili powder; 2 tsp. garlic powder; 1½ tsp. cayenne pepper; 12 skin-on, bone-in chicken thighs (about 4 lb.); Zest and juice of 2 lemons; 4 tsp. Diamond Crystal or 2½ tsp. Morton kosher salt; 5 Tbsp. Barbecue Seasoning, divided; 1 Tbsp. vegetable oil, plus more for grill; 1 small onion, finely chopped; 3 garlic cloves, finely chopped; 2 Tbsp. light brown sugar; ¾ cup ketchup; 2 Tbsp. apple cider vinegar; 2 Tbsp. unsulfured blackstrap molasses; 1 Tbsp. Dijon mustard; 1 Tbsp. Louisiana hot sauce; 1 Tbsp. Worcestershire sauce