Minimum requirements to force module rebuild

I am trying to build my plugin, My project builds successfully, however in one of my header files - no changes I make in the code are reflected in the editor. It will sometimes be resolved with a rebuild, but i cant do this after every change. I have already tried generating project files and deleting the regenerating binaries, but neither worked. The header file is being included and changes have been tracked at some point. But now it will not track any changes I make to it.