This is the example usage of electron-packager that I never found online anywhere else.
To add resource.exe and resource2.dll in the resource folder when you create an installer, this is how you do it with the --extra-resource commandline switch.
electron-packager . --overwrite --asar --extra-resource="resource1.exe" --extra-resource="resource2.dll" --platform=win32 --arch=ia32 --icon=./frontend/dist/assets/icon.ico --prune=true --out=./build --version-string.ProductName='Hot Pan de sal'
within the backend code you can refer to the files as: