Wash the parsley, dab dry and pluck the leaves from the stalks. Chop parsley finely, except for a few leaves for garnishing. Season tomatoes with salt and pepper. Fold in parsley.
Grate cheese. Drain corn and pineapple. Cut pineapple slices in half. Cut flat bread in half horizontally. Spread halves thinly with tomato sauce. Cover with pineapple slices, ham and corn. Sprinkle cheese evenly on top.
Place flatbreads on 2 baking trays lined with baking paper and bake in a preheated oven (electric range: 225 °C/ convection oven: 200 °C/ gas: level 4) for approx. 10 minutes until golden brown. Remove flatbread from the oven.
Garnish with parsley and serve immediately.