The endothermic gas reaction takes place in two steps or stages. In the first stage, some of the methane. burns with air creating an exothermic (heat generating) reaction. In the second stage, the surplus methane. reacts with the carbon dioxide and water vapor produced in the first stage. This second stage is endothermic. (heat absorbing).
Pat the chicken drumsticks dry with clean paper towels. Cover them with plastic wrap or aluminum foil to warm them up to room temperature for 30 minutes. Preheat a gas or charcoal grill to 400 degrees F. If you are using a charcoal grill without a temperature gauge, this will take about 20 minutes.
Start the Traeger grill on Smoke with the lid open for 4-5 minutes to establish the fire. While waiting, season the brisket on all sides with Prime Rib Rub (reserve 1/2 tablespoon of the seasoning for later use). After the brisket has smoked for 2 hours, remove to a large sheet of plastic wrap.