Greaseproof paper is made from unbleached paper for use in the kitchen. It is especially useful when dealing with fatty foods like bacon and salami. While the grease in those foods might seep through normal parchment paper, it does not get through greaseproof paper. Greaseproof paper can be used in several different ways.
Wrap foods in a sheet of greaseproof paper before storing them in a freezer or refrigerator.
Place cold food on a sheet of greaseproof paper and place it in a microwave. Greaseproof paper is safe to use in the microwave.
Wrap greasy foods in a sheet of greaseproof paper before packing them into a lunch box. Items like leftover pizza may be too greasy for normal paper, but are fine for greaseproof paper.
Place a sheet of greaseproof paper over the top of a jar or container that is missing a lid. Wrap a rubber band over the paper to secure it to the top of the container. This can keep foods from spoiling.
Spread a thin layer of baking grease on top of a sheet of greaseproof paper. Then use the paper to line cooking tins and baking trays that will be used in the oven.