Some pizza dough recipes say you must add a yeast sachet but others say just use flour and eggs. Which is best?
There are a few different types of pizza base and the recipe you choose to use is mostly dependent on the amount of time you have and the ingredients to hand. Nigella's Crustless Pizza (from Kitchen) uses a batter base that is made from eggs, flour and milk. It is slightly more like a baked Dutch pancake or a Yorkshire pudding than a pizza, which is why it is called a Crustless Pizza. It is very quick to make, as the base ingredients are whisked together, and quick to cook.
Most traditional pizza bases are a bread-type base that is made with flour and yeast and the yeast is needed to help the dough to use and to create a lighter crust. This type of base obviously needs more time as the dough has to be kneased after it is mixed, then needs time to rise, be knocked back/punched down and shaped before cooking. There is also "scone base" type of pizza which is made with some butter rubbed into flour and then bound into a soft dough with a little milk. This is then shaped and baked and again is a quicker form of pizza than the traditional yeasted base, but has a softer, more crumbly texture.
Nigella also has some short-cut pizzas using ready-made breads such as the Naan Pizza from Kitchen and on the NIgella website.