Working with Yelp API.
Had a working method to return Restaurant List in a separate project.
Moved that code to a new project.
Spent 3 hours trying to figure out why the tried and true method was returning an empty list.
I forgot I had also made a helper method in that other project to turn km into meters.
Instead of searching a 5km radius, I was searching a 5 meter radius...

(Prior to that I mixed up my longitude and latitude, and searched for pizza places in the antarctic. Spoiler: There are none.)