Energy efficiency has become a primary concern for data centers in recent years. Understanding where the energy has been spent within a software is fundamental for energy-efficiency study as a whole. In this paper, we take the first step towards this direction by building an energy profiling module on top of IgProf. IgProf is an application profiler developed at CERN for scientific computing workloads. The energy profiling module is based on sampling and obtains energy measurements from the Running Average Power Limit (RAPL) interface present on the latest Intel processors. The initial profiling results of a single-threaded program demonstrates potential, showing a close correlation between the execution time and the energy spent within a function.