SO cool. You just need 1 cup of grated (raw) cauliflower, 1 cup of cheese and 1 egg. You can increase the amount of cauliflower if you want to as well but maybe think about using an extra egg or a little more cheese.
Just mix it all together and then put it in the oven for 15-20 minutes to bake and then add all your toppings and pop in back in there until it's ready to eat!
Important things to do are use a tray with edges and make sure that the base isn't too thin, if it's too thin then it'll just fall apart. Good luck!