Mix the yeast or baking soda and lemon juice with the sugar in 650ml of luke warm water. Add the flour and salt to a large mixing bowl and make a well in the middle.
Add a little of the water to the well in the middle and slowly bring in the flour from the edge and mix it into the water with a fork. Keep adding the water and stirring in until you have a sticky dough.
Dust some flour on a work surface, remove the dough from the bowl and knead the dough pulling it back and forth and pushing it with the heel of your hand for about 10 minutes
Put the dough back into the bowl, dampen a clean cloth with cold water and cover the dough. Leave it to rise at room temperature for at least 1 hour
Pre-heat the oven to 250°C/500°F/gas mark 9. Remove the dough and divide it equally according to how many pizzas you are making. Dust a clean surface with flour and roll each one into a rough circle about 3 - 4 mm thick
Place the base on a pizza tray if you have one, or a baking tray or lightly greased tin foil. The pizzas won't change in size when cooked so you roll the same size as the pizza tray. Cover the base with passata, then sprinkle on the fresh basil then a thin covering of grated mozarella. Add any other toppings.
Place the pizza in the oven and cook for 7-10 minutes until golden and crispy.