Pre-heat the oven to 200ºC (400ºF) Gas 6.
Measure out the flour, baking powder, salt and xanthan gum in a large bowl. Add the grated cheese and mix together. In a separate bowl, combine the crème fraîche and the milk, then pour into the flour mixture and combine with a fork until you get a sticky dough. Turn out onto a floured board.
To make individual small pizzas
Gently knead the dough using a little more flour until it holds together and then roll it out to about 1.5 cm (1/2 in) thickness. Using a 7.5 cm (3 in) floured round cutter, cut out rounds and place these on a baking sheet. Bake in the hot oven for about 10 minutes until the pastry is crisp and golden.
To make a large pizza
Press the dough out into a circle measuring about 7 inches across. Don't worry too much about the thickness just try to keep the thickness of the dough even. Place the circle of dough in your pizza pan and then press it into the pan using your knuckles, Try to make the dough the same thickness throughout so that it rises evenly in the oven. Don't worry about the indentations left by your knuckles. These will make the pizza look more authentic! If you like a thick crust, use all of the dough. If you prefer a thinner crispy crust, then use about 2/3 of the dough. Use the remainder to make a few small pizzas which you can pre-bake and then put in the freezer for a rainy day. Pre-bake the base for about 15 minutes.
If you are making your pizzas straight away, then once the bases are out of the oven, add your toppings and then put them straight back in the oven for another 10–15 minutes until golden and bubbly. Serve immediately.
If you are putting the bases in the freezer than leave the bases to cool completely, before you pack them in an airtight container or plastic bags. You do not need to wait for these to defrost before cooking. Simply add your toppings and put in a hot oven. Your baking time may be a little longer.
To make dough balls
Prepare a baking sheet with non stick lining paper. Pinch off pieces of dough and roll into a smooth balls. Place them on the prepared baking sheet. Bake in a preheated oven 200 C for about 15 minutes until the balls are just turning golden. Remove from the oven and brush with garlic butter. Serve immediately.