When Little Nettle was a toddler who refused to sleep past four in the morning, Bake Club was born and one of the first things we made were sweet potato biscuits from Isa Chandra Moskowitz’s Appetite for Reduction. Sweet potato biscuits pretty much became a staple in this house, which is awesome as I am an unabashed fan of both sweet potatoes and biscuits.
One morning we only had purple sweet potatoes, but we figured we’d give it a go. We were surprised and delighted to discover that the biscuits were not only a beautifully vibrant purple but they were also flecked with a bright turquoise blue throughout! It’s a replicable result: an interaction between the anthocyanin (the purple pigment) and the baking powder. If you want a fun baking science experiment to do with your tiny sous chef - or on your own - this is a good one.