Some foods cause you to peak later...pizza for instance. I can eat it and have a good 2 hr post meal reading, but at the 3 hr it goes high.
Doc usually recommend testing 2 hrs after the first bite, as that's the time it usually takes for a non-diabetic to return to their pre-meal level. Our goal is 140 or less at that point. Personally, I don't worry as much about my peak on a daily basis as I do the 2 hr reading being at a acceptable level, though I will check at regular intervals when testing a new food.
You could find your peak by eating and testing at 30 minute intervals after that meal.