Chicken Baked in Foil with Sweet Potatoes and Radishes (Finish and Serve)

Recipe from The Make Ahead-Cook by America's Test Kitchen, 1/4 c extra virgin olive oil, 6 garlic cloves sliced thin, 1 tbsp grated fresh ginger, 1 tsp toasted sesame oil, 1/4 tsp red pepper flakes, 12 oz sweet potatoes peeled and sliced crosswise 1/4 in thick, 4 radishes trimmed and quartered, 2 celery ribs, quartered lengthwise and cut into 2 inch lengths, 1/2 large red onion sliced 1/2 inch thick layers separated, kosher salt and pepper, 4 (6 ounce) boneless skinless chicken breast trimmed, 2 tablespoons rice vinegar 2 tablespoons cilantro