I just made the most wonderful doughnut muffins. The full recipe can be found
here. The first review at the bottom shows the modifications I made. If anyone wants the scaled recipe, just let me know.
These were great and I was able to switch the sugar in the topping to Splenda without problems. However, I would like to reduce the butter amount in the topping. My first thought was just to thin it with hot water. Is there a downside to that? Is there something else that I could use that would make the sugar (or Splenda)-cinnamon coating adhere?