Prepare the Blueberry Zinfandel BBQ Sauce. Pour the wine in a medium saucepan and bring to a boil, reduce heat and simmer over medium heat until the wine is reduced by half, about 5 minutes. Pour into a bowl and set aside.

Put the blueberries and the maple syrup into the same saucepan, mash slightly with a potato masher or wooden spoon and bring to a simmer over medium heat. Cook, stirring frequently, until the mixture is reduced by half, about 5 minutes. Add to the bowl with the reduced wine.

Heat the olive oil in the same saucepan over medium heat. Add the onion and garlic and saute, stirring occasionally, until onions are translucent, about 5 minutes. Add the reserved wine and blueberries, ketchup, cider vinegar, worcestershire sauce, mustard, salt, cinnamon and cayenne. Bring to a simmer, reduce heat to low and cook, stirring occasionally, until the mixture is thickened slightly. Reserve. This sauce can be made up to one week in advance.

Make the chicken. Preheat the oven to 425 degrees F, with a rack in the top ⅓ of the oven. Spray a half sheet pan with cooking spray. Season the chicken with salt and pepper. Scatter the red onion, sweet potato cubes, blueberries, and thyme sprigs over the pan. Arrange the chicken on top of the vegetables and drizzle the olive oil over everything in the pan. Place the pan in the oven rack and roast for 35 minutes. Remove the pan from the oven and brush the chicken liberally with the Blueberry Zinfandel Sauce. Return the pan to the oven and continue to bake until the chicken has an internal temperature of 170 degrees, about 20-25 minutes longer.

Remove from the oven and serve with additional Blueberry Zinfandel BBQ Sauce.