You did it! We figured this one out! It is a truth universally acknowledged (by me for certain) that the Bitchery pretty much knows everything, and really, it's true. Scroll down to see the solution for this HaBO - and many thanks!

Kristy sent me this HaBO request that made me laugh way too loud:
I read it as a teen/young twenty-something, so lets say it was from some time in the 90's.
It was a historical western. I have absolutely no memory of the hero – he must not have impressed me much. But the heroine was blond (I think) and pretty bad ass. She owned a ranch of some sort and it was in some sort of danger. The thing I remember most about this story is that she had a dog. A giant Great Dane named PU or p.u. or peuh! I don't remember how she spelled it – but she meant p.u. like “stinky”.
Anyway, she was some kind of masked vigilanti, but our hero ended up recognizing her by her Great Dane dog. That's all I got. Anybody else remember the stinky Great Dane and the vigilanti blonde?
Historical western with vigilante blondes and stinky Great Danes? I kinda want to read this – and am definitely happy to know that it exists. Anyone recognize this book? Is the dog really that stinky?

Does PU have a descendant named Ace? (Attached image from Ambush Bug #3, August 1985.)
Ace was wiped out of continuity (at least once) but not due to stinkiness as far as anyone knows.
I have no ideas about this book but I LOVE the ACE pic.
I think I read this one. Oh geez. No idea at all of the title though. Now it’s going to drive me crazy 😉
OMG, I’m sure I’ve read that too, but it’s been waaaay too long ago and I can’t remember either title or author. I just looked at my bookshelves, but I guess it’s long gone. IIRC, the heroine’s family farm was attacked by bandits when she was younger and she survived by hiding in the hayloft (maybe?) but watched them all die (except maybe a sister?). This is why she becomes badass later. It’s possible I’m mixing up a couple of books but I definitely remember the dog and how the hero figured out who the vigilante was by the dog. It seems to me like he actually talks her out of killing one of the bandits near the end of the book and letting the law prevail instead. I’d love to know if this one ever gets figured out!
Yes! I remember that part now. She watched her family die a horrible death at the hands of Bad Guys. (Just like Batman, which brings us back to Ace from the first comment. I think we just opened a worm hole you guys!)