Bilad al-Sham Kitchen - Grilled chicken with thyme in a foil packet

"Recipe Ingredients:

1 whole chicken, cut into pieces½ cup olive oil¼ cup lemon juice¼ cup vinegar¼ cup sumacSalt and pepper4 cups fresh thyme3 onions, sliced2 potatoes, sliced with skinTaboon bread for servingSpecial oven bags"