Are you laughing? Probably. But I promise you that a plastic knife, such as this one from Chez Wendy's, is a must-have in your kitchen. I've found that nothing works better to cut brownies, bar cookies, tarts, single-layer cakes, and more. For some reason the plastic glides right through the food being cut without grabbing and tearing at it like other knives. And better yet, it can be totally free. Now that's a pretty awesome kitchen gadget!