Fresh herbs in cocktails are always a pleasant surprise, and the mint in this julep is certainly no exception. You'll begin by muddling it in a pitcher, which brings out its delightful aroma and flavor and therefore infusing the alcohol with more mint flavor. Just be careful not to smash the leaves with too much force, or you'll end up with a slightly grassy aftertaste. Though the fresh peach slices are technically an optional garnish, if you're serving this to guests, it's worth the extra effort. Not only does it make for a gorgeous presentation, but everyone will enjoy having a fresh peach slice to munch on.