BOT Zane found the toast while trying to complete the job on Death Wish - attempting to complete the Like Turkeys Voting for an Early Christmas and Riders On the Snowstorm achievements.
Sadly, BOT Zane's crew was unsuccessful on that day.
But the following day, BOT Zane tried out a new crew and finished the achievements, but without the Toast.
After that, BOT Zane farmed White Xmas on Normal, looking specifically for the Toast. After about an hour, the Toast manifested itself for BOT Zane's second time. Being on Normal, and due to BOT Zane's dodge build, he was able to finally earn the achievement: Impossible, It Can't Be. Is it?
The first encounter with the Toast:
The second encounter: