The reliable prediction of the turbulent combustion processes in lean flames is nowadays of crucial importance in the design of gas turbine combustors. This work presents an assessment of the capabilities of Flamelet Generated Manifold (FGM) in the framework of Large-Eddy Simulation (LES), as implemented in the commercial CFD solver CONVERGE. One of the main characteristic of the code is the Adaptive Mesh Refinement (AMR) technique, namely the use of a dynamic mesh where elements size varies during the simulation. For validation purposes, the TECFLAM swirl burner, consisting of a strongly swirling, unconfined natural gas flame, has been chosen. Results highlight the advantages of AMR in describing turbulent flames, leading to a successful prediction of the main characteristics of the reacting flow field.