Mint can bruise easily on the cutting board. It also browns quickly after being cut. The trick to getting a nice “chiffonade” cut on your mint lies in only allowing your knife to run through the leaf once. To do this, try stacking your mint leaves on top of one another, with the largest mint leaf on the bottom of the pile. Roll the leaves together tightly lengthwise, as if you are rolling a cigar. You can then slice this rolled up bundle of mint leaves widthwise, in tiny slivers.