In this research, we provide first experimental evidence on the dissolution of a thin compound layer sandwiched between the parent materials when it is heated below the order-disorder temperature. The Ta(10 nm)/TaV2(6 nm)/V(30 nm) system, prepared by DC magnetron sputtering, has been chosen to prove the expected simulation results. The samples were investigated mainly by secondary neutral mass spectrometry. The about 6 nm thick TaV2 compound layer was dissolved by annealing at 1025 degrees C for 1 h. Then, it was reformed by increasing the annealing time to 2-3 h. These results prove our previous computer kinetic Monte Carlo and Kinetic mean field calculations. These findings are important for nanotechnologies utilizing early stages of solid state reactions.