Heat the oven to 200°C/180°fan/gas mark 6.
Tear the pitta into shards, place on a baking tray and toss with 1 tablespoon of olive oil. Bake for about 15 minutes until crisp, then set aside to cool slightly.
Crush or grate the garlic and put in a jar with the lemon juice, vinegar, oil and sumac. Season with salt and pepper and shake well. Leave to infuse until the salad is ready.
Cut the tomatoes into chunks, they don't all need to be the same size.
Cut the cucumber into rough dice.
Finely slice the spring onions.
Top and tail the radishes and cut them into quarters.
Pick the leaves of the flat leaf parsley and mint and roughly chop.
Combine the tomatoes, cucumber, spring onions and radishes in a large serving bowl. Stir in the herbs.
Toss the dressing with the salad, then, just before serving add the pitta and a final sprinkling of sumac.