I keep seeing these butterflies on cakes & cupcakes. They seem pretty popular & are very cute. What are they? Cut outs? Where can I buy the cut outs to make these?

they are PME plunger cutters. You can get them individually or in a set of 3 different sizes. Very easy to work with you can bend poster board and set them in the bend to dry and get the wings set. reasonably priced too.

Try GSA.