Guessing a food name from 150 years ago?

There is a record that in 1884, George Foster, a US Navy officer, visited Jeonju and received incredible culinary hospitality for 3 days and 2 nights. Among the many dishes, George recorded that the "red serrated cake" was particularly amazing. I wonder what food that could be... It might be a dish that no longer exists... No matter how much I think about it, I can't figure it out..