To do this without any pry plugins (I was having troubles with pry-stack_explorer), just look at caller.
I actually look for my project name to filter out all the irrelevant rails stack items. For example, if my project name were archie I’d use:
caller.select {|line| line.include? "archie" }
Which gives me the stack trace I’m looking for.
A shorter way would be:
caller.select {|x| x["archie"] }
Which works just as well.