Preheat the oven to 200oC, gas mark 6. Unroll the pastry sheet and put on a large parchment-lined baking tray. Deeply score a 2cm border around the edges and prick the base all over with a fork. Cook for 15 minutes, then set aside to cool for 5 minutes.
While the pastry is cooling, beat the ricotta in a mixing bowl with the lemon zest, garlic, parmigiano reggiano and shredded mint and basil leaves; season. Press the base of the pastry down, leaving the borders raised. Spread the ricotta mixture evenly over the base.
Arrange the tomatoes over the ricotta, season, drizzle with the oil and scatter with the nigella seeds. Cook for a further 25-30 minutes, until the pastry is crisp and golden. Cool for 5 minutes then scatter with extra basil leaves. Slice to serve.
Cook’s tip
If you prefer, you could scatter chopped black olives over the tomatoes instead of the nigella seeds
