First, we frosted a batch of cupcakes in Joey's school colors. My go-to cupcake recipe is Starlight Yellow Cake from Betty Crocker (1991). To make a graduation hat cupcake topper, just invert a small peanut butter cup, and affix a chocolate square with a dollop of frosting. You could also use chocolate dipped cookies, but the ones I found at the store were too rectangular, so the chocolate squares worked better for us. We snipped up some Fruit by the Foot for the tassel. We melted a bit of chocolate to stick the tassels to the mortarboards.
Happy Graduation, Joey!!