Make a hole in the dry ingredients (yeast, salt, sugar, flour) and add the wet ingredients. Mix with a spatula until it doesn't help anymore and switch to your hand.
Knead adding a bit of flour at a time until it doesn't stick to your hand.
Put a bit of olive oil in a bow and rotate the dough to cover it. Put a kitchen towel on top and let rest for an hour or until it has doubled in size. In the meantime, we go to pre-cooking some of the toppings.
Put the toppings that need pre-cooking on an oven-safe dish and mix. Then put in the oven at 180C for about 15-20min or until the onions are soft and the tomatoes have let their juices escape.
Spread the dough using your hands on top of a baking tray lined with baking paper. You can also use a rolling pin but I rather have the rustic look. Try to have it nice and thin, to about 3mm.
Put the cheese first, spreading the grated mozzarella and parmesan and then laying out small dollops of the ricotta. Don't make them too large or it will moisten the dough.
On top of that scatter the pre-cooked ingredients.
Bake at 200C for 15min or until nice and golden
Cut up and serve warm