Prepare the pizza sauce a in a small bowl.
Thinly slice the peppers and onion.
Preheat the oven to 180C degrees. Line a large baking sheet or pizza base with parchment paper.
Unroll the pastry and place it onto the baking/pizza sheet.
Using a silicon brush, spread the pizza sauce all over the pastry, leaving a thin rim for the crust. Arrange the sliced veggies on top, then scatter the chickpeas, chilli and reserved lemon, then put the baking sheet in the oven.
Bake for 15-25 minutes (in the middle of the oven) until the crust is golden. Do check that that the pastry is cooked through - the base should not be soggy!
Serve warm or at room temperature with plenty of freshly ground pepper and chopped mint scattered on top.