1In 1-gallon resealable food-storage plastic bag, mix water, 2 tablespoons kosher salt, 2 tablespoons brown sugar and the beer. Add drummettes. Seal bag; place in large bowl. Refrigerate at least 8 hours but no longer than 24 hours.
2Heat oven to 375F°F. Line 15x10x1-inch pan with foil. Remove chicken from brine; discard brine. Rinse chicken thoroughly with cool water and pat dry with paper towels. Place chicken in pan.
3In small bowl, mix 3 tablespoons brown sugar, 3 teaspoons salt, the garlic powder and pepper. Brush oil over chicken. Sprinkle with rub mixture.
4Bake uncovered 45 to 55 minutes, turning after 25 minutes, or until chicken is no longer pink in center.