Heat the oil in a pan and fry the potato pancakes in portions for about 6 minutes while turning. Drain on kitchen paper. Wash, clean and slice the tomatoes. Drain mozzarella and tuna. Cut mozzarella into slices. Pluck the tuna into bite-sized pieces.
Place the potato pancakes on a baking tray lined with baking paper. Cover with tomatoes, mozzarella and alternately with salami and tuna. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 10 minutes. Sprinkle pizzas with pesto. Arrange on plates, garnish with basil and cherry tomatoes