This inquiry-based experiment is designed for organic or biochemistry undergraduate students to deduce the identity of phospholipids extracted from chicken eggs and dietary supplements. This is achieved using thin-layer chromatography (TLC) data, a series of guided questions of increasing complexity, and provided relative retention factor (Rf) values for phospohlipids. Colorful visualization agents are used that selectively reveal phospholipids with specific functional groups on TLC plates. The novelty in this experiment lies in the students' ability to use the colorful patterns on the developed plates and compare the spot locations to a list of Rf values without the need for phospholipid standards. Furthermore, the use of krill oil and fish oil provide a unique aspect where an additive purported to be a good source of phospholipids, krill oil, is tested against fish oil (seemingly similar, yet negative for phospholipids). A prelaboratory assignment familiarizes students with concepts of TLC and phospholipids. The experiment takes two, 3 h laboratory periods to complete, but with specific modifications, can be completed in one, 3 h period.