For my two doods we still watch 'em like a hawk ( 8 months old). I had an Old English Sheepdog who was very smart (I know, I know, OES aren't the brainiest dogs in the world, but Bailey was sharp!). He would wait till I turned my head and SILENTLY steal stuff off the counter. Once he ate a pound of cream cheese. He had diarrhea for two weeks. Later he stole a butcher knife. It was getting very dangerous. My vet suggested I "bait" him with butter or cheese left on the counter but covered with cayenne pepper. It took three experiences for Bailey to get enough. I felt so sorry for him and I worried that it was cruel... but he NEVER got on the counter again.
Because I had had this experience I watch my doods very carefully and I don't allow them to even show interest in my food or the kitchen counters. As soon as the nose goes up in the kitchen to sniff, they get a verbal correction or a shake from the noisy can. (We keep an empty soda can with a couple of nickels inside out on the counter - they HATE the noise it makes when you shake it.)
I believe that you establish yourself as your dog's leader in all sorts of behavior issues, when you tap into their natural instincts to respect the alpha's food. That's why I correct as soon as I see the nose go up. Once their paws are on the counter, I know I've lost the battle!