In a large bowl combine the flour, salt and baking soda mix together. Add olive oil and mix until crumbly. Now add water mix with hands until the dough comes together in to a dough.
That is soft but not sticky, if necessary add a little more water. Now knead for 5 to 7 minutes until it is soft and smooth. Divide the dough into 5 equal pieces and shape into balls and covered with cling wrap and let it about 30 minutes.
Heat the pan, roll the dough into a disc roughly 8 inches in diameter and pricking with a fork. Place the rolled dough on the hot pan. Cook the bread high medium heat for 2 to 3 minutes on each side.
Remove the piadina from the pan and cooking the remaining dough.Top with salad leaves (lettuce, Ice berg etc) zucchini slices, tomato and fresh mozzarella and sprinkle salt and pepper. Drizzle with extra oil and fold in half.
Serve immediately.
