Gently fold in zucchini and ricotta and season with salt and pepper.
Heat oil in a 20cm diameter frypan (with metal handle) over medium heat. Pour in zucchini mixture and cook for 5-6 minutes until just set around the edges but still runny in the middle.
Remove from the heat and place under the grill about 6cm from the heat source for 2-3 minutes until golden brown and just set. Remove from the grill.
Cut into wedges and serve. Serve frittata with cherry tomatoes sprinkled with basil leaves and freshly cracked black pepper