Add the onion to a small jar or bowl and pour over the balsamic vinegar. Set aside and allow the onions to steep in the vinegar until required.

Using a pair of metal tongs place the peppers directly on the flame of a gas hob. Allow to char then turn over until they are charred all over. Transfer carefully to a zip-loc food bag and seal. Then set aside for a few minutes, this will make them easy to peel. You can alternatively do this under a hot grill.

Drizzle the bread with a little olive oil and toast on both sides on a hot griddle. Remove to a plate, immediately slice the garlic clove in half and rub each slice of bread all over with the garlic. Cut the bread into large 1" cubes.

Remove the peppers from the bag, they should be cool enough to touch. Using a table knife scrape away the skin and chop roughly.

Add the pepper, bread pieces, mozzarella, basil leaves, onions and vinegar to a large serving bowl. Drizzle with a little extra virgin olive oil and toss together.