I think it would probably take a couple of hours, with a lot of that time being spent on the brewing stage.
Immediately after writing that I thought "what if you use a microwave instead". Which, honestly, does make sense. I think you'd need a different recipe, in the same way you get different food recipes for microwaves. You also can't actually fit a lot in a regular microwave, which would make it save less time than you'd think.
I'll also add that like cooking, the you can cut things down with good prep.