In a large saucepan, heat oil over medium-high heat. Add mushrooms and garlic; cook stirring frequently until mushrooms are tender and liquid evaporates, about 5 minutes. Stir in chili powder; cook and stir 1 minute. Add chicken broth, stewed tomatoes, kidney beans, and corn. Bring to a boil; reduce heat and simmer to blend flavors, about 10 minutes. Serve topped with tortilla chips, if desired. Makes 2 servings.