Flan flop or flan fail means to utterly suck at making flan. Here are some examples:
Exhibit A - Lopsided flan.
Exhibit B - Over-steamed, air bubbly flan:
Exhibit C - Pile-o-mess flan
But...after some burnt sugar and a couple dozen eggs later, oh and maybe loosing some sense of reality for two weeks, I finally made not thee perfect but comes close to what I envisioned my type of flan should look and taste like...silky, creamy, and custardy:
Thank you to Globe Express for graciously being my tasting panel.