Dissolve the yeast in warm water and stir in a pinch of flour, cover with a kitchen towel and let rise for a few minutes. Make a well in the middle of the flour and add the yeast dissolved in water and mix everything well. Mix in the coarse sea salt and the cooked and grated potatoes.
Knead the dough well. If necessary, add a little more warm water. Shape the dough into a ball and let rise covered in a warm place for 2 hours.
Grease a baking sheet well with olive oil. Portion the dough as desired and roll out 1 cm thick. Press the garlic cut into pieces into the batter. Mash halved cherry tomatoes on the dough or spread chunky tomatoes on the dough. Season with oregano and fine sea salt. Spread plenty of olive oil over the dough.
Preheat the oven to 250 ° C (top / bottom heat). Place the baking sheet on the second rail from the bottom and reduce the temperature to 225 ° C. Bake for about 20-25 minutes until the desired browning is achieved.
The focaccia is halved with fresh mozzarella or mortadella like a sandwich or just like that with a little salad and herb butter - very filling.