Ask HN: Any good software for generating ATC templates?

Specifically Given, When, and Then scenarios where there are test procedure steps and following expected results. Where I work we do this in an Excel spreadsheet, using a strict format. It's pretty annoying because I've asked around and people don't seem to know where the origin of this spreadsheet is. So we end up copying the previous one, inevitably destroying it over time. I just want some web app, user creates a test plan, in that document they add a test case and text fields appear that they fill in. I'd love to make one myself, but I know something this simple's been done numerous times. It would be a shame for me to write up some amateur tool that gets rejected when there's something professional out there that upper management would find more compelling.