No I am not talking about lines. That is a whole different story! I am talking about a baking term. When you "cut in," you are mixing a solid, typically shortening or butter, into flour or some other dry mixture. You "cut in"" until the solid looks like tiny peas. When you incorporate this fat into the flour correctly, the result is flaky perfection! You can use 2 knives or try a fork, but a pastry blender is best. Mine is from Pampered Chef. I have had it for years. I think it is was inexpensive at the time, maybe $5-$6. Want deleciously flaky biscuits or scones? Use the right tool and learn how to cut in properly.