Place the flour, dried yeast, salt and 2 tablespoons of the olive oil into a food processor and pulse for 3 seconds. Pour in most of the water and turn on again, mixing till you have soft dough. Add the remaining water if needed to bind the dough. Turn the dough out onto a floured work surface, and knead the dough till soft for at least 5 minutes. Form into a ball. Grease a large bowl with some of the remaining olive oil and place in the dough. Brush the top with some more oil, cover with cling film, and leave to rise for 45 minutes, or double in size. In the meantime, heat 1 tablespoon of oil in a pan and add in the sliced red onions, sugar and balsamic vinegar and sauté for 15 minutes to soften and caramelize the red onions. When the dough is ready, turn it out onto a floured surface and knock out the air, flattening the dough. Cut the dough into 4 equal pieces. Roll each piece out into an oval shape and place them onto a floured baking sheet. Drizzle the top of the pizza`s with the remaining olive oil and sprinkle over the caramelized onions. Arrange the anchovy fillets on top, then finally crumble over the feta cheese and sprinkle over the coarse salt. Leave the pizzas to rise again for 20 minutes, before baking in the oven for about 25 minutes at 200`c, or until the pizza`s are golden brown and cooked through. Serve the rosemary pizza`s with caramelized onions and feta cheese either warm or cold.