Place a large soup pot over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the peppers, onion and garlic, and cook, stirring every now and then, for 3-4 minutes, until the veggies start to get tender.
Add the balsamic vinegar, chicken stock and crushed tomatoes to the pot and bring up to a bubble. Add the bread pieces right from the freezer, some salt and pepper, and simmer for 10-15 minutes, stirring every now and then. Let the soup thicken –- when you can stick a spoon in it, it's done!
Taste and re-season with salt and pepper. To serve, garnish each portion with some of the torn basil leaves and pass some grated Parmigiano Reggiano at the table.