In a large cooking pot, add chicken broth, ginger root, and peppercorns, and bring to boil. Reduce heat to low and simmer uncovered for 20 minutes. Strain broth, discard ginger root and peppercorns. Return strained broth to pot. Add green onions, red pepper, mushrooms, bamboo shoots, rice wine vinegar, chili powder, and sesame oil. Simmer for 10 minutes or until vegetables are just tender. Serve in soup bowls over cooked white or brown rice.