- Set your grill to about medium heat and brush the grates until they are clean.  
- To make the rosemary-infused bbq sauce, whisk the ketchup, butter, Worteceshire sauce, maple syrup, chili powder and rosemary in a small saucepot. 
- Heat the rosemary-infused sauce over a medium-high flame; once it is boiling, decrease the heat to medium-low and cook it for 5-7 minutes, periodically stirring until it thickens up.  
- Whisk the kosher salt, pepper, lemon pepper, smoked paprika, cayenne pepper, garlic powder, and onion powder in a small bowl. 
- Pat the chicken wing drummettes dry with paper towels and place them into a large bowl.  
- Add the olive oil to the chicken wing drummettes, toss to coat, then generously apply the seasoning blend and toss to combine. 
- Place the wings onto the grill in an even layer, cover them and cook for 30 minutes.  
- Baste the chicken wings with the rosemary-infused bbq sauce, place the lid back onto the grill, and cook for another 30 minutes.  
- Continue to baste the wings with the sauce until they are slightly charred and reach your preferred doneness.  
- Toss the chicken wing drummettes with any remaining rosemary-infused bbq sauce.  
-  Serve and enjoy!