In a large stewpot, sauté onion, carrots, and bell pepper in oil for 3 minutes; add the mushrooms and cook 3 minutes more.

Add the turkey, oregano, chili powder, cumin, and pepper and cook, breaking up ground turkey, until meat is no longer pink.

Add the remaining ingredients, stir well, and simmer over low heat for 30-45 minutes, stirring occasionally.

You can garnish individual bowls of stew with shredded cheese, a dollop of sour cream, and some fresh parsley or cilantro if desired.