If stored properly, your frosting will keep for about 3 weeks. Just place it in an airtight container and stick it in the refrigerator.  Since this homemade frosting lasts for a good amount of time, this is the perfect recipe to prepare in advance! Once you’re ready to use your frosting, take it out of the refrigerator and let it come to room temperature. You may need to give it a good stir or a quick run through the mixer to get it back to that original perfect, fluffy texture.