@ossobuco,
Yeah, I don't know anything for a fact either. Nothing stands out as being a possible problem except the cookie dough. Had a pretty boring day. Cereal for breakfast, water to drink throughout, I think leftover stew for lunch (no problem eating it for dinner the night before and no problem when the rest of the leftovers were eaten later... warmed up thoroughly, etc.).
Still undecided what to do in the future -- as always, trying to calibrate that line between not taking unnecessary, significant risks and not being an anal-retentive worrywart (which has its own drawbacks). Right now maybe leaning towards using Eggbeaters for recipes that might involve spoon-licking.