Heat oil over medium heat in a large pot. Saute garlic and onion until soft. Add oregano, chili powder, broth, water, and tomotoes. Bring to a boil and simmer
for 5 minutes. Stir in chiles, hominy, cilantro, beans, chicken and corn. Simmer an additional 10 minutes. Spoon soup into serving bowls. Top with cheese, green onions and crushed tortilla chips. Serves 8.