Followup:

It's been about 24 hours now since my "cheat" and my BG has definitely returned to the "normal" range as it was 91 after my walk today.

My keytone test strips, which have always been dark purple, between the "large" and "extra large?" colors on my test bottle, were between "medium" and "large" this AM and has remained unchanged this afternoon. Thud123 was correct it seems that the reaction was a bit delayed, but it appears I did not thow myself out of ketosis by just eating one single meal and a snack with carbs.

To be totally honest, I must also say that the meal did not stay with me long. As often happens when I eat Chinese or Sushi, it does have somewhat of a laxative effect. Don't get me wrong, it did not make me sick, but lets just say by this morning it was pretty much out of my system. The results may have differed if I'd had something like ice cream.