Blanch tomatoes in large pot of boiling water for 1 minute. Drain. Rinse under cold water to cool and drain. Using small sharp knife, peel off skin. Cut tomatoes into quarters and remove seeds. Puree tomatoes in blender or processor.
Heat 2 tablespoons olive oil in heavy large saucepan over medium-high heat. Add bell pepper and saute until almost tender, about 3 minutes. Stir in garlic and tomato paste; cook 2 minutes. Mix in tomato puree, thyme and hot pepper sauce. Remove from heat. Cover and let stand at room temperature 2 hours.
Heat remaining 3 tablespoons olive oil in heavy large skillet over medium heat. Add fennel; zucchini, green bell pepper, mushrooms and celery. Saute until crisp-tender, about 8 minutes. Season with salt and pepper.
Bring soup to boil. Season to taste with salt and pepper. Ladle soup into bowls. Top with vegetable mixture. Garnish with basil and serve.
Source: Amphycles (Bon Appetit, May 1991) Typed for you by Karen Mintzias