Preheat grill on medium-high Whisk the egg and garlic together in a large bowl Gently fold in the zucchini and ricotta and season with salt and pepper
Heat the oil in a 20cm-diameter non-stick frying pan over medium heat Pour in the zucchini mixture and cook for 5-6 minutes or until frittata is set around the edge but still runny in the centre
Cook under preheated grill about 6cm from the heat source for 2 minutes or until golden brown and just set Remove from grill and cut the frittata into 8 wedges and place on serving plates
Divide tomatoes among serving plates and sprinkle with basil Serve immediately