I haven't given toast yet (my mom did though, and she seemed to do ok), but DD does get waffles. She has no teeth yet, and I just give her the Eggo cinnamon toast waffles. They are perforated into 4 squares (maybe 2" by 2"?) and I give her one whole square at a time. She does great with it! Sometimes she gets a big chunk, but she has not problem mashing it.
DS didn't get his first teeth until he was over 14 months old, and I always felt like I couldn't feed him anything but purees....so I didn't. I'm finding out differently with this one, and probably wouldn't have even tried it if she didn't grab a piece while I was splitting one up for DS and shove it in her mouth before I could stop her!
That said, I would never leave her alone with it, I make sure I stay there and watch her, just in case.