Does anyone know of an app that will work on a windows tablet that will cast videos stored on the tablet (large ones like movies) to an Amazon firestick?

I've tried with no success with VLC and I am looking for something fairly simple to use.

Plex is one program you could use.

It's free on the Amazon Fire stick and for Windows.
It doesn't 'cast' as such, but you set it up as a media server on the Windows device, which you can then play on the Fire stick.

That's presumimg the Windows tablet runs full Windows, so can run the desktop program?
There is a Plex app in the Windows Store, but I haven't tried that, so don't know if it has full server functionality?