Prepare a cake pan 28 cm in diameter or a rectangular one 20 x 30 cm, or a heart-shaped pan 23 x 23 cm + additionally a second smaller pan about 20 cm in diameter.
Peel the potatoes, rinse, cut in half and cook until soft. Drain, mash with a masher into smooth puree and cool (cover so they don't dry out).
In a large plastic bowl or mixer bowl, crumble fresh yeast or add dried yeast. Pour 100 ml warm water, add sugar and mix. Set aside for 5 minutes, then add sifted flour and mix. Add the cooled potatoes and combine with your hands or mixer paddle.
Add 70 ml warm water and knead the dough for 10 minutes with your hands or mixer hook (the dough will be quite firm). Add 3 teaspoons sea salt dissolved in 4 tablespoons warm water. Continue kneading for approximately 10 minutes. Finally, thoroughly knead 3 tablespoons extra virgin olive oil into the dough, cover with a cloth and set aside in a warm place to rise for approximately 2 hours.
Grease the cake pan with olive oil and place the dough (about 2 - 3 cm high). Cut the cherry tomatoes in half, remove the stems, sprinkle with salt, pepper and 2 - 3 teaspoons oregano, mix with 2 tablespoons extra virgin olive oil. Arrange the tomatoes on the surface of the dough with cut side up, pressing them gently into the dough. Keep approximately 3 cm spacing between individual tomatoes. Set aside to rise for approximately 30 minutes.
Preheat the oven to 200 degrees C, place the focaccia in the oven and bake for 35 minutes to a lightly golden color.
