If you over-bought those delicious hard, deli cheeses for your guests and have lots of leftover slices, don’t worry, you can keep them fresh by spreading a little butter on the cut sides of each piece. Wrap in plastic and store in your refrigerator. The butter seals in all the moisture so the cheese won’t dry out. The best cheese to try this on is semi-hard ones like Swiss, Edam, Cheddar, and Gouda.