I have bred broken to broken but they both have blanket color and borderline too much color and not enough white, but i knew it was risky. I've had a solid to a broken throw dilute before as well. This was with Hollands, not Frenchies, but I would guess it's fairly close to the same. I've gotten Chestnut from a black and Orange/fawn(not completely sure) cross, i would try breeding them over to the fawn, i don't think that it would come out unshowable.
A friend of mine accidently crossed an opal mini rex to a fawn holland lop(She was told they were both girls, mini rex wasn't) and got chestnut babies, so you might pull chestnut, fawn/orange.