Sunflower wedding favors - why not cookies you lovingly prepared well ahead of time? Freeze your pre-baked cookies (completely cooled) up to two months by placing them in single layers separated by sheets of waxed paper. Make sure your container is airtight. Here is an easy to follow tutorial of how to make sunflower cookies. After baking or thawing out your sunflower cookies, it will take you two days to complete - one for flooding (covering the cookie with a thin coat of royal icing), and the second for piping the edges of the petals and the little green dots.