Heat oven to 240C/220C fan/gas 9. Tip the pizza mix into a bowl and make up following pack instructions. Cover the bowl with a cloth and leave for a few mins.

Meanwhile, mix the tomato pure with 4 tbsp water, 1 tbsp oil from the tuna and some seasoning.

Knead the dough for a few mins on a floured surface, then halve and put each piece, spaced apart, on a large oiled baking tray. Press with an oiled hand to make thin flat pizzas they dont have to be perfectly round.

Spread with the tomato pure mixture, then top with the tuna, capers, cheese and olives. Bake for 10-12 mins. Serve scattered with the onion and rocket.