Place browned wings and onions in a 5 quart stockpot. Add water to roasting pan and stir, scraping up any brown bits on the bottom of the pan. Pour the the water from the pan into the stockpot. Stir in 6 cups broth, carrot, and thyme. Bring to a boil. Reduce heat to medium-low and simmer uncovered for 1-1/2 hours.