Place the flour in a bowl, make a hole in the middle and break up the fresh yeast. Slowly pour in the lukewarm water, the salt and start kneading. Continue until you have obtained a smooth and stretchy dough which you will then allow to raise for at least two hours. In the meantime boil the potatoes then let them cool, peel them and slice them. Divide the dough into two balls and roll them out flat. Place the
first sheet on a baking tray, after greasing it.
Place the pesto, then a layer of potatoes, bits of stracchino and chopped walnuts on top.
Place the second sheet of dough on top, seal the edges and place bits of stracchino on top.
Bake at 180°C for about 40 minutes.