I have been eyeing this recipe for a while, but finally made it on Christmas Day. I made a few small substitutions. For example, I rarely use all-purpose flour. Instead, I used a mixture of oat flour and white whole wheat. I do not like nuts in brownies, so I added almost 1/2 cup of chocolate chips.
I had one 'issue.' I used vegan semi-sweet chocolate chips and they did not melt entirely once the boiling water was added. I added additional water, but still the chocolate did not melt completely. Finally, I was concerned that I was adding too much water, so I put the bowl in the microwave to melt the chocolate.
I am a bit of a 'brownie snob,' but I was very happy with these brownies. Thank goodness since the recipe is somewhat complicated. This was my 3rd vegan brownie recipe attempt and the most successful. Thanks Mattie!