We are the same - Max is 18 months, and seriously we now think he has learnt to open the kitchen bin....apparently what is in there is better than whats in his bowl LOL. Easily solved, just have to remember to take the rubbish out every night....no matter how little is in the bin.....
Last night I came downstairs to find him half in the microwave eating the cooked chicken I had put aside for DH and my dinner, apparently I hadn't latched the door......
This works every time for us: set some basic mousetraps, place them gently upside-down onto counter-tops, then carefully place a sheet of newspaper over all of them. As soon as a cat touches the paper or walks on it, the traps will go off making a big noise and scaring the kitties off the counter. Eventually you can leave the UN-SET trap on the counter as a reminder, and pretty soon you won't need anything.