Make the dressing by whisking together the oil, za’atar, lemon juice, salt and pepper. I like to put them in a lidded jar and shake until they emulsify.
Halve the tomatoes and put in a large mixing bowl with the basil leaves and thinly sliced red onion.
Add half the dressing and mix well.
Spread the rocket over a serving plate and pile the tomato and basil mixture on to the centre.
Scatter the cheese over the top then pour a little more dressing over. You may not need all the dressing but it keeps well in the fridge for several days.