Photoshop optionally with Quixel. Substance is neat, but I dislike the lack of direct control, and I’ve seen far too many new (and not so new) artists using it as a crutch because it’s so easy to select a material, drop it on a model, change a few sliders, and think they’re done.
This is an old tutorial, and while the workflow is from before PBR was a common thing, it covers a lot.