Heat large pot or dutch oven over medium-high heat, add oil then turkey. Cook turkey, breaking apart until no longer pink, ~5 minutes. Add onion, garlic, and squash, and cook, stirring occasionally, ~5 minutes.

Add bulgar, oregano, cumin, coriander, salt, and pepper and cook, stirring, ~1 minute to bloom spices. Add beans and chiles.

Add 1/2 cup stock and deglaze pot and cook down liquid by half. Add remaining stock, bring to a boil, then cover and reduce to a simmer. Cook 45 minutes to thicken chili and develop flavors. Serve with a dollop of plain yogurt or sour cream.