If you don’t have whole wheat pastry flour, you can use all-purpose. I would not recommend using regular whole wheat. Additionally, I have made this by substituting coconut butter for the full amount of butter. It was just as delicious, albeit slightly drier. You cannot taste coconut at all. Finally, take into account the power of your microwave. Mine has a mind of it’s own and is insanely powerful, so I cooked this on 80% power. Judge accordingly and add/subtract a few minutes of cooking if you know your's is wonky too. Unfortunately it may take 1-2 trial runs to get the right consistency because all microwaves are different, but I promise it’s worth it!