Remove the ends of the zucchini and discard. Slice the zucchini lengthways so that you have two strips each about 1/4 inch thick. Season the zucchini with a pinch of salt and pepper and drizzle with half a tablespoon of olive oil. Rub the oil and seasoning into the zucchini.
Step 2
Heat a griddle pan over a high heat. Place the zucchini strips in the pan and cook for 2 minutes or so each side until just tender and char lines appear.
Step 3
Thinly slice the tomato and the mozzarella and arrange alternating pieces across the griddled zucchini. Season with a little salt and pepper.
Step 4
Roughly chop the basil and scatter over the open sandwich. Drizzle with the remaining olive oil to serve.