I was thinking maybe Brassicaceae, they tend to be rosette-forming and to have purpling. The closest I've found, but still not quite a match, is Streptanthus cordatus. It has the sparsely toothed leaf margins and somewhat winged petioles of the ID plant (not quite spatulate I think?) but it doesn't have all the hairs of the ID plant. Here's a pic in case it gives someone a lead:
https://www.google.ca/search?q...
