Method
Prep:2hr20min  ›  Cook:35min  ›  Ready in:2hr55min 

1. First make the pizza dough. If using dried yeast, dissolve the sugar in 75 ml (2½ fl oz) of lukewarm water, then sprinkle the yeast in and set aside for 10-15 minutes until it is frothy.
2. Meanwhile, sift the flour and a pinch of salt into a large bowl and add the easy-blend yeast, if using. Make a well in the centre and add the olive oil and 125 ml (4 fl oz) of lukewarm water if using easy-blend yeast, or the frothy yeast mixture and 50 ml (2 fl oz) of lukewarm water. Stir with a wooden spoon to form a dough.
3. Turn out the dough onto a lightly floured work surface and knead for 5-10 minutes until it is smooth and elastic, adding extra flour, 1 tablespoon at a time, if necessary to stop it sticking; if it is too dry, add extra water, 1 tablespoon at a time.
4. Shape the dough into a ball and grease the cleaned bowl with a little oil. Put the dough into the bowl, roll it around so that it is lightly coated with oil and loosely cover the bowl with cling film. Leave the dough to rise in a warm place for 1 hour, or until it has doubled in size.
5. Meanwhile, to make the topping, bring a large pan of water to the boil. Add the onions, reduce the heat and let them simmer for 10 minutes, or until they have softened, then drain well.
6. Put the onions into a large nonstick frying pan with the sugar, balsamic vinegar, and salt to taste. Cook them over a medium-high heat, stirring, for 10 minutes, or until the liquid has reduced but not dried out completely. The sugar should have caramelised slightly and the onions should have a rich flavour. Stir in the marjoram and some black pepper and adjust the seasoning if necessary.
7. Turn out the risen dough onto a lightly floured surface, punch it down and knead it for 2-3 minutes. Return it to the bowl, cover it once more and set aside for 30 minutes for the dough to rise again.
8. Meanwhile, heat the oven to 240°C (475°F, gas mark 9). Lightly grease two baking sheets.
9. Turn out the dough, punch it down and divide it into two pieces. Shape each piece into a ball, then roll it out into a 25 cm (10 in) circle and place on a baking sheet. Drain off any liquid from the onions, then spread them evenly over each pizza and sprinkle with the feta cheese.
10. Bake for 12 minutes, or until the cheese has melted and the edges of the pizzas are crisp and golden. Serve them straight from the oven.
11. Tip: for added flavour, cook the onions ahead of time and use their cooking water as the liquid in the pizza dough.

Low-fat tip

Cooking the onions in sugar and balsamic vinegar gives them a rich flavour without adding fat.