Since they can vary slightly in thickness / moisture, you may need a tablespoon of non-dairy milk to adjust the overall thickness of the batter depending on which you choose. (feastingonfruit.com)
Now I already know the proper thickness of batter so when I find it too thick I simply add milk untill it's right and the outcome is always delicious. (simplyrecipes.com)
And again which you choose will affect the overall thickness of the batter, so adjust with a tablespoon of non-dairy milk if you opt for the nut butter unless your nut butter is very runny. (feastingonfruit.com)