If you don't want to crate him while you are out then you need to do a quick "dog proofing" of the house to make sure any food left out is put away or out of reach. Once a dog learns that counter surfing means delicious food, he'll do it again and again.
As far as teaching leave it, you can definitely teach and reward it with positive reinforcement. Here's an example video: Teaching Leave-it
However you can't tell the dog to "leave it" when you're not around so management is the key (meaning you need to put away food if you are leaving the room or can't watch him). The less he practices the behavior the less it'll happen.
Counter surfing can also mean boredom. Taking him out more and giving him doggie puzzles is always a fun way to keep dogs busy and out of trouble. Things like the Kong and other puzzle toys that hold food (Buster Cube, Tug a Jug, etc) work well.
Edit: If you catch him in the act of something you can use an interrupter like clapping your hands or making a loud noise. When he looks up you either lure him or put him on the ground and give him something else to do and redirect.
As far as teaching leave it, you can definitely teach and reward it with positive reinforcement. Here's an example video: Teaching Leave-it
However you can't tell the dog to "leave it" when you're not around so management is the key (meaning you need to put away food if you are leaving the room or can't watch him). The less he practices the behavior the less it'll happen.
Counter surfing can also mean boredom. Taking him out more and giving him doggie puzzles is always a fun way to keep dogs busy and out of trouble. Things like the Kong and other puzzle toys that hold food (Buster Cube, Tug a Jug, etc) work well.
Edit: If you catch him in the act of something you can use an interrupter like clapping your hands or making a loud noise. When he looks up you either lure him or put him on the ground and give him something else to do and redirect.
