A plethora of lipids exist in living organisms that perform various functions ranging from cell membrane formation, to energy storage, and signaling. To rationalize lipid functions and characterize the dynamic adaption of cellular lipid structures to external stimuli, the field of lipidomics thrives to detect as many lipids as possible and decipher their molecular architecture in one sample. This endeavor, however, is a demanding bioanalytical task as subtle changes in the molecular makeup of lipids often hinder unambiguous annotation of lipid structures and reliable predictions of lipid isomers are complicated by the intertwined nature of enzymatic processes involved in lipid metabolism. For example, cells adapt their phospholipid fatty acid (FA) composition to their needs in a biochemical cascade termed Lands cylce. In this cycle, attachment of FAs to lysolipids occurs with the help of lysophospholipid acyltransferase enzymes. Whereas the involved enzymes in the Lands cycle are mostly known, their specificity and selectivity have not been studied in detailed. Zhao et al. recently showed that upregulation of phosphatidylcholine (PC) 18:1/16:0 in tumor tissue is indeed connected with the increased lysophosphatidyl acyltransferases-1 (LPCAT1) expression compared to surrounding healthy material showcasing the need of structurally resolved lipidomics workflows. For this reason, multiple new methods have been developed that that track lipid structure changes, mainly relying on mass spectrometry (MS). Sensitive detection with direct infusion methods, or shotgun MS, of lipids has been implemented on multiple state-of-the-art mass spectrometric platforms. By electrospray ionization (ESI) detection of hundreds of lipids is routinely feasible by making use of high mass resolution and mass accuracy capabilities of modern MS instruments. To resolve the structural complexity of lipid mixtures, hyphenation of MS methods with separation systems such as liquid chromatography (LC) or ion mobility spectrometry (IMS) can facilitate disentangling complex samples. LC-MS and shotgun MS lipid annotations additionally make use of tandem mass spectrometric methods to reveal lipid class and FA composition.