Carefully? Professionally? Except which knife stall at which farmers market wants the job? Learning to sharpen the (correct) knife (for the task) will do as mu

Carefully? Professionally? Except which knife stall at which farmers market wants the job? Learning to sharpen the (correct) knife (for the task) will do as much or more for the chef who struggles here. Prepping 1000 lemons? An ultrasonic knife is not your answer.