I've made this twice, the first time with Bob's Red Mills gf baking flour and the second time with King Arthur gf 1-1 flour. Not sure if it was the flour or making sure not to overmix but they turned out better/more flaky the second time. The dough was quite gooey and difficult to keep together when cutting out the biscuits the second time in an attempt to not overmix and I think they did rise better because of that. I also flipped them over after 15 minutes and baked another 5 minutes on the other side which worked well (the bottoms were starting to get a bit dark but the inside wasn't quite done yet). I also brushed them with butter when they were done. They were very tasty and quick to make!
Also note it says to cut up your butter into small pieces and place in the freezer so it stays cold when mixing in. I would do that step right at the beginning. It's further down in the instructions and so I had to wait around the first time.
