Learn to live with it and clean off the counters before cooking? If you think about it, cat butts and paws aren't always perfectly clean and can make couches, floors, laps, etc. "unsanitary" as well (but no one is telling the cat to keep its grubby paws off the carpet!). Make sure you don't leave anything potentially dangerous to the cat on the counter because she probably goes on it when you're not home.
On my gas stove, the knobs need to be depressed before they can be turned, which I don't think a cat (or my cats, anyway) could manage. You could also buy safety covers for them (a quick google shows they can be found at hardware stores, baby stores, and Amazon has quite a few choices as well).