<<Disclaimer: Verify this information before applying it to your situation.>> I recently purchased this book, Author is Roben Ryberg. I made the Buttermilk Loaf and followed the recipe to the letter. I was very excited when I took it out of the oven because it was nice and brown and had risen beautifully. Within four minutes or so it had deflated to about three inches tall. She uses a base of potato starch and cornstarch for all her recipes. Anyone else used this cookbook and what were the results? Thank you, Leila, Australia