Mix the yeast, warm water, and vegan sugar. Leave that for like 10 minutes. Add the rest (flour, salt, olive oil) and just mix it.. if its too wet you might want to add more flour. Cover with Glad Wrap (or Cling Film, or whatever you feel like calling it) and put it in a warm place to rise for like 5 minutes (or until the potatoes are cooked, Or just don't even do that because I don't really think it makes much difference).
Peel the potatoes, cook them (by microwave is easiest). Mash them (You may want to add a bit of soymilk + vegan margarine, and even some salt)
Roll out the base to the size you want (It doesn't make a very big pizza,