New potato & rosemary focaccia

Cook the potatoes in boiling water for 15 mins, then drain and leave to cool completely. Meanwhile, boil the kettle.

Pour 175ml boiling water and 100ml cold water into a large bowl. Sprinkle over the yeast, 1 tsp salt and 2 tbsp olive oil. Mix well, then stir in the flour, adding a splash more water if the mixture feels too dry.

Turn out the dough onto a clean work surface and knead for 15 mins until smooth and elastic (dust the surface with a little flour if the dough is sticky), then shape into a ball. Grease the inside of a large bowl with olive oil, then add the dough to the bowl and turn a few times to coat in the oil. Cover with cling film and leave in a warm place for 1 hr or until doubled in size.