I'm sure this is simple: how to re-render a composite node?

Sometimes I leave the Use Nodes un-checked in the compositing window.
I hit render only to realize at the end that all my passes that were supposed to be rendered in the proper folder are just not there. From what I see, though, Blender did all the calculations that my nodes required. So, I guess the data is there only need to be saved.
Is there a way to trigger the file output operation in the compositing without re-rendering everything?

For a moment I thought was the auto-render option but that’s not it.
Any idea?

Try using a file output node, I used the compositor a while ago and I think that solved it.

Hm… I have file output nodes but it’s not working.
I’m also forcing refresh by pressing CTRL + SHIFT + Click on the last node which is indeed recalculating the node tree but still, no output happening.

Is it really not possible to simply save what it’s already cached?

I think its like a one time execution in blender. So you might have to re render.

Yes, I think you’re right. It seems that’s the way it works. It’s a bummer.