So yesterday I made the pizza base again - I had planned to replace the ground almonds with coconut flour, thinking the latter is lower in carbs. I checked the labels before starting cooking, and would you believe it ground almonds are lower carb than coconut flour after all!
I had assumed ground almonds would have the same carb count as whole almonds - but they have much less. That strikes me as incredibly odd- the carb content for ground almonds per 100g is around 6, and for whole almonds around 23! What's that all about?!!! Does the grinding process remove a load of carbs or something?
I ended up using about 150g of ground almonds, and topped up to the required 170g using 20g of coconut flour. this worked and my dough was much thicker despite using milky mozzarella.
The recipe says you can use mozzarella or Edam - I've added some Edam to my Christmas Tesco shop and will try with that as well (as well as making a mental note about finding hard mozzarella. You live and learn)!