I would say the microwave, but that's too easy and used so often, it's really shouldn't be included. So for me, my mini-food processor is really what I am most grateful for, especially when it comes to chopping onions. My sister got my this about 3 years ago and at first I was like, "What do I need this for?" She mentioned the onion thing, and after the first time I used it I knew my food prep experiences would never be the same.