Honey-Glazed Chicken, Peach, and Sweet Potato Skewers

medium sweet potato (about 3/4 lb), peeled, sliced into 1/3-inch rounds

sherry vinegar

plus 1 Tbsp honey

olive oil

Salt

Freshly ground black pepper

boneless, skinless chicken breast, cut into 16 pieces

peaches, pitted, halved, and each half quartered

small red onion, cut into 1.5-inch chunks

pecans, coarsely chopped

ground cumin

pumpkin pie spice