Roughly chop the heirloom tomatoes, onions, cucumber, red bell pepper, garlic, basil and cilantro and add to a large non-metallic bowl.
(Optional step, you can grill your tomatoes first on a nonstick griddle for a few minutes to further sweeten them and to get some nice charred edges- this adds a smokier flavor).
Crumble the white bread over the tomato mixture.
Add in half of the olive oil, tomato juice, red wine vinegar, balsamic vinegar, cumin, salt and red pepper. Stir to combine.
Cover with plastic wrap and chill for at least 4 hours, preferably overnight, to let the flavors develop.
Ladle the tomato mixture into a blender and blend on high until smooth.
Place a fine mesh sieve over a large bowl. Carefully pour the gazpacho into the sieve and use the back of a wooden spoon to push the soup through the sieve.
Discard the large chunks and rinse the sieve.
Place the strained soup back into the blender and blend a second time.
Strained the soup again through the sieve.
Cover the strained gazpacho with plastic wrap and chill for 2-3 hours to allow the flavors to further develop.
When ready to serve, give the gazpacho a good stir. Ladle the gazpacho into chilled bowls. Top with diced tomato, cucumber, cilantro and other toppings of your choice.