Mix yeast and sugar for 30 seconds until liquid, then stir in 400ml of water and 4 tbsp olive oil.
Combine flour and salt in a large bowl, add the yeast mixture, and stir to form a soft dough.
Knead the dough on a floured surface for ten minutes until smooth and elastic.
Place dough in an oiled bowl, cover, and let rise in a warm place for 1.5 hours until doubled.
Preheat the oven to 220°C.
Knead the risen dough for five minutes on a floured surface to knock it back.
Shape into two circles, place on baking sheets, and prove for 15 minutes.
Form dimples with fingertips, brush with 2 tbsp olive oil, and sprinkle with coarse salt and rosemary.
Bake the loaves for ten minutes at 220°C.
Reduce heat to 190°C and bake for 25-30 minutes until golden.
Cool slightly on a wire rack before serving.