Make croutons: Preheat oven to 375 degrees F. Put diced cubes on a baking sheet and bake until golden brown, about 10 minutes.
Roast red pepper: Roast red pepper under broiler until charred on all sides. Place in a paper bag and let steep until cool. Remove from bag and remove skin and seeds. Chop.
Make soup: In an electric blender, combine one tomato, one cucumber, half the onion, 1 quarter each of the green and yellow peppers, roasted red pepper and 1/3 cup regular tomato juice. Blend, covered at high speed for 30 seconds to puree the vegetables.
In a large bowl, mix the pureed vegetables with remaining tomato juices, 1/4 cup olive oil, the vinegar, Tabasco, salt and black pepper.
Refrigerate mixture, covered, until well chilled — about 2 hours.
Rub inside of small skillet with garlic (keep garlic). Add rest of oil. Sauté croutons in oil until flavored and browned. Remove from heat and set aside.
Coarsely chop remaining tomato, cucumber, onion, green and yellow pepper. Put each of the chopped items and croutons in separate bowls. Crush reserved garlic. Add to chilled soup, mix and serve immediately. Serve gazpacho in individual bowls with a sprinkle of chives on top. Have your guests add additional vegetables, croutons as toppers. Offer additional hot sauce for those who want an additional kick.