Preheat the oven to 220°C, fan 200°C, gas 7, and lightly grease a large baking tray with oil.
Make the pizza base mixes, following instructions on the pack. Roll the dough out to 2 circles, each measuring approximately 20cm in diameter.
Spoon 4 tablespoons of the passata over each base, leaving about a 1cm border.
Place the shredded ham, chopped mushrooms, sweetcorn and mozzarella on one half of the base. Brush a little water around the edge of the dough and fold in half to enclose the filling.
Transfer the calzone to the tray and bake for 20 minutes until golden. Cut in half and serve with the cucumber, sliced pepper and cherry tomatoes on the side.
Cook’s tip: you can use any ingredients you like for the filling that you like. Just make sure you shred any meat and chop any vegetables finely.