In large saucepan heat oil over medium heat; Add mushrooms, leeks, potato, garlic, oregano, basil and red pepper flakes; sauté about 5 minutes. Add water and corn; bring to boil and cover. Lower heat and simmer about 5 minutes or until vegetables are tender. Stir in tomatoes, salt and pepper. Bring to boil; lower heat to simmer for about 10 minutes or until hot. Stir in parsley if desired.
Variation: Garnish with low fat grated mozzarella or Parmesan cheese.