We start by pouring the yeast, water and sugar substitute into a bowl. Leave aside for 15'.
In a large bowl, beat with a mixer 1/2 cup olive oil, the flour and the yeast mixture. As soon as they come together a little, transfer them to a smooth surface and knead. Transfer to a bowl after first smearing it with olive oil and put it in a warm place for 1 hour.
Uncover, pour 1/4 cup olive oil in the pan where we will bake the focaccia. Pour the dough on top and spread it with your hands. At the end we also make dents with our fingers.
Cover with film and put back in a warm place for another hour.
Preheat the oven to 200C in the air. Bake for 15-20 minutes.
As soon as it comes out of the oven, brush the entire surface with olive oil and sprinkle rosemary and salt on top.