Okay so it didn't turn out quite right - probably a yeast blooming problem - but it still tastes great!
I'll try and figure out another batch in the breadmaker tomorrow. (And yes it's just standard food coloring. I haven't found natural colorings that I like or don't cost a fortune.)
Cross-posted from Dreamwidth ( http://nimitzbrood.dreamwidth.org/244988.html ) but feel free to comment here as well.