Mix the flour with the yeast and salt in a mixing bowl. Stir in the water and half the olive oil and mix to a dough. Cover with a tea towel or cling film and leave in a warm place to rise for approx. 45 minutes until doubled in size. Turn out the dough onto a floured surface and knead well until smooth and elastic. Knead in half the onion and rosemary.
Roll out the dough, to fit the Remoska. Place in the Remoska on a circle of Magic Non-Stick Liner. Press into the surface with the knuckles to make small depressions in the dough. Prick the dough several times with a fork. Brush with olive oil and sprinkle with some coarse sea salt and the remaining onion and rosemary. Cover and leave in a warm place to rise for 15 minutes. Bake for approx. 30-35 minutes until golden and cooked through. Serve warm.