Pour the warm water bowl of a heavy duty food processor fitted with a plastic blade and sprinkle over the yeast.
Leave for 10 minutes to start the yeast activating. Sieve the flour and salt together and add to the water.
Process until you have a soft ball of dough (add more flour or water as necessary).
Process the dough for one and a half minutes, in 3 x 30 second bursts, resting the dough for a minute between each burst. (The dough can also be mixed in an electric mixer fitted with a dough hook, mixing for about 8 minutes or knead by hand for 12 minutes).
Lightly oil a bowl and roll the dough around in this until it is coated.
Cover lightly with glad wrap, tea towel or a plastic bag and leave to rise in a warm, draught free place for 1 hour.
You can use the dough now, or for more flavour development, punch back, knead a few more times and leave to rise again for another 40 minutes.
Heat a pizza stone or baking tray in the oven to the hottest it with go.
Slice open the sausages and pinch of large peas sized portions and set aside.
Heat the oil in a large frying pan and sauté the mushrooms with the garlic and a good sprinkle of salt for a few minutes until most the liquid has been evaporated.
Divide the dough into 2 pieces.
Stretch and roll out the dough on a floured board.
Arrange the sausage meat, mushrooms and garlic over the bases.
Top with the mozzarella, oregano and chilli flakes if using then season with salt.
Drizzle with a little extra virgin olive oil and bake for about 8 minutes until crisp and bubbling.
Slice and top with fresh rocket leaves and cherry tomatoes and another drizzle of oil and chili if liked.