Add the extra virgin olive oil, yogurt, Farmer's Pick Concord Grape 100% Juice, thyme, bay leaf and garlic into a large sealable plastic freezer bag. Add ½ tsp salt and ¼ tsp pepper to the marinade and stir to combine. Add the chicken pieces and marinate for 30 minutes, or up to 4 hours.
Remove the chicken from the fridge 20 minutes before cooking. Remove pieces from the marinade and pat them dry; set aside on a clean plate. Meanwhile, submerge 4 skewers in cold water for 10 minutes; this helps prevent flare-ups on the grill.
Onto each skewer thread a piece of chicken followed by a grape, repeat until the chicken and grapes are used up. Meanwhile, preheat a lightly oil grill over medium-high heat.
Transfer the chicken skewers to the grill and cook for 4 minutes per side until completely cooked, about 16 minutes total. Let the skewers rest for 10 minutes before serving.