Put the flour into a mixing bowl and add the yeast, oil, salt and black onion seeds.  Add enough warm water to bind to a soft dough. Beat with the flat of the hand until the dough forms a ball and leaves the side of the bowl.  Set on a floured work surface and knead for 5 mins.  Rub the mixing bowl with a little oil, put the dough in the bowl and set aside in a warm place.  

Brush a baking tray with olive oil and pre heat the oven to 200C/400F/gas mark 6.   

Peel, quarter and core the pears. Cut each quarter into three or four slices.  Put the pears into a bowl, add the apple juice or vinegar and stir until coated.   

Put the Ricotta into a bowl.  Season with black pepper and stir in the herbs and half the Parmesan cheese.   

Roll the dough into a rectangle or 2 x 15cm rounds and lift onto the baking tray.  Spread the Ricotta mixture over the top.  Arrange the pear slices on top of the Ricotta.  Crumble the Feta cheese and scatter over the top of the pears. 

Scatter over the remaining Parmesan cheese.  Cut the Kalamata olives in half and arrange over the top.  Bake for 20 minutes or until the top is golden brown and the dough crisp.