Gabbi Shaw/INSIDER As part of an ongoing taste test series, INSIDER tried four different fast food restaurants' hot coffee. We tried Chick-fil-A, Wendy's, McDonald's, and Dunkin' Donuts. Wendy's, a relative newcomer to the breakfast game, was our favorite. All four are a solid option though, if you're looking for a cheap caffeine jolt. Here at INSIDER, we've done our fair share of taste tests, including fried chicken, French fries, and chocolate chip cookies.