Preheat the oven to 210C/415F/gas mark 6. First, prepare the fennel. Brush both sides of the fennel slices with oil. Lay them on a parchment-covered baking tray. Sprinkle with salt and pepper. Roast for 20-30 minutes, turning every 10-15 minutes, until softened.
To make the dough, combine the water, salt, and half a tbsp of coconut sugar in a jar with a tight-fitting lid. Shake until the salt and sugar dissolve. Add the vinegar and shake lightly.
Sift 200g of the flour into a large bowl, then add the bicarbonate of soda, 4 tbsp of olive oil, and the remaining sugar. Gradually add two-thirds of the sugar, salt and vinegar mix, stirring to combine. The dough will be quite liquid at this point.
tart sifting more flour into the bowl, 25g at a time, mixing it in with a wooden spoon as you go. It is important to add the flour just a little at a time; if not, it may become too stiff, which will be hard to fix, even by adding more liquid. When the dough is no longer too sticky to be kneaded by hand. Dust your hands and the surface of the dough with flour and knead quickly for 2 minutes. The dough should be very soft and may still be slightly sticky at this stage.
Divide the dough in half and shape each piece into a ball. Put each ball on to the centre of a piece of cling film and flatten into a disk with the palm of your hand. Cover with more cling film and refrigerate for at least 30 minutes or overnight.
Set the oven to 200C/400F/gas mark 6. Dust a rolling pin with a little flour. Roll each piece of dough on a separate piece of parchment paper into a 6mm thick circle. Brush with oil. Bake for 10 minutes, one crust at a time.
Remove from the oven and top with the fennel, then the figs and cheese. Make sure that you cover the dough completely with topping, or it will dry and harden. Bake for another 12 minutes, one pizza at a time. Top with the fennel fronds and other greens and some black pepper. Let cool slightly before slicing.