Personally I hate this question.

And I get it in every interview. Somehow my brain just doesn't care to remember the gritty details for tough bugs. I'll spend days on a bug but soon after I solve it I'll only remember the actionable takeaways like "next time I should try using X tool sooner" or "check your assumptions on Y part of the stack".

I think it's because I never spend any time revisiting that bug in my mind. I've got new problems to solve. You need to revisit something to remember it.