Rinse chicken inside and out. Pat dry with paper towels. Place chicken in a foil roasting pan. Sprinkle with 1 Tbsp. kosher salt and 1 tsp. black pepper.
Place on center of grill. Turn center burners off (if you have 3 or more burners). Reduce outer burners to medium low. Close grill. Grill 15 minutes per pound.
While chicken is cooking, place carrots in a bowl. Peel beets and cut into large chunks. Add beets to carrots in bowl. Peel sweet potatoes, and cut into chunks. Add sweet potatoes to bowl. Peel onions and cut into quarters. Add onions to vegetables in bowl. Add olive oil and toss to coat.
Spread vegetables on a baking sheet. Sprinkle with remaining salt and pepper. Bake at 400 for 30-40 minutes.
*Notes regarding this recipe: If you don’t have a gas grill, you can roast the chicken in the oven: Heat oven to 350, prepare chicken as directed above, and bake at 350 for 15 minutes per pound.