Training cats to not jump onto your counter top, bench, table or desk is something that should be undertaken as soon as the behavior starts.
Cats are naturally inquisitive creatures and love to know what is going on and what their favorite person is doing.
They can no doubt also smell the food you are preparing and will want to check it out.
They also love to be made a fuss of, usually immediately, so will jump up and rub against you when you are peeling vegetables or setting the table.
Finding scraps or leftovers will encourage them to jump up as the behavior brings a reward in the form of food.
I love both my cats but if they jump up onto food preparation or eating areas they are put down immediately and told no in a firm voice.
Making a noise with some marbles in a tin or spraying with a little water will have them jumping down quick smart.
Yelling or hitting your cat won't stop any undesirable behavior, it will only make them frightened and wary of you.
And will most likely make them jump up onto those areas when you aren't around anyway.
It will be necessary to make sure that there is nothing on your counter to entice your cat up there when you're away.
No lovely smells, no food or leftovers or plates to lick.
If you suspect your cat is checking the counter out when you're not home, try putting some double sided sticky tape on it or use a citrus spray.
Cats will avoid both of these.
My daughter used to love having her cat Tikki on the desk in the office when she was watching DVDs or working on the computer.
In winter it was a nice warm spot as we have an oil filled heater under the desk.
In summer, she was at the level of the fan.
When my daughter moved out of home for work reasons, it was left to me to change Tikki's behavior as I didn't really want her there (not enough room) and I didn't want stray cat fur getting into my laptop (she is a long haired cat).
It didn't really take long to retrain her.
Each time she jumped up she was told no and put down again.
I would give her a pat as she was missing my daughter and wasn't able to get onto a favored place (the desk).
I then moved to saying no as she was about to jump up, and stroking her while she was still on the ground.
Sometimes I removed her from the office by picking her up and stroking her then putting her on my bed.
It only took about a week.
I didn't have to 'bribe' her with special cat treats.
I was firm and consistent.
While it is still better to train your cat while it is still a kitten, it is possible to retrain older cats.
She still comes into the office to 'talk' to me and when she wants grass seeds that she can't get to removed.
The key when training a cat, even an adult one, is to be consistent, persistent and gentle.
Let them know just who runs the house.