Served with a tangy, purple sumac sauce, these gluten-free turkey meatballs include a secret ingredient that's plentiful in late summer—shredded zucchini. Gretchen McKay/Pittsburgh Post-Gazette/TNS
They can be made with almost any type of ground protein—including poultry, beef, pork, and lamb—and sometimes there’s no meat at all. Instead, they’re rolled together with legumes, beans, grains, mushrooms, and/or a whole host of vegetables.