Step 1: For the poolish, place the warm water and yeast in a small bowl and leave to sit for 1 minute, before stirring to dissolve. Stir the flour into this yeasted water until smooth and elastic. Cover with plastic film and leave in a draft-free place for 1 hour or until doubled in size.
Step 2: For the final dough, place the flour and salt in the bowl of an electric mixer fitted with a dough hook. Stir the 1/2 teaspoon yeast and poolish mixture into the flour. Using the dough hook, slowly add the water and knead until a soft, elastic dough forms. Generously flour a spot on the kitchen bench, tip the dough out and knead it by hand for 5 minutes, using only enough flour to stop the dough from sticking to the bench.
Step 3: Brush the inside of a large bowl with Olive Oil and roll the dough in the bowl to coat with oil. Cover the surface of the dough with plastic film and leave in a warm place to rise for about 1–2 hours or until it has doubled in size.
Step 4: Knead the dough again, adding the chopped rosemary in Oil then divide it in two (each piece should weigh about 900 grams). Dust two proofing baskets with flour or oil two 1 kilogram bread tins, then place the dough pieces in them and shape to fit. Place each basket or tin in a plastic bag, seal and leave in a warm place to rise for 1–2 hours or until doubled in size. If making flatbread instead of loaves of bread, halve the dough, dust the working bench with flour and roll and stretch to the shape of the tray approximately 28 centimetre x 44 centimetre. Dot with the olives creating a dimpling effect. Leave for half an hour to rise just a little before baking.
Step 5: Preheat oven to 230C and bake for 15 minutes; turn over if needed and return to oven for a further 10 minutes at 180C. Take out of oven to rest on a wire tray, brush top immediately with Extra Virgin Olive Oil.