01 -
Set oven to 350ºF (177ºC) and prepare a cookie sheet with parchment paper and nonstick spray.
02 -
In a medium bowl, whisk together all-purpose flour, baking powder, and salt until evenly blended.
03 -
In a separate bowl, beat salted butter, shortening, and granulated sugar until mixture is light and fluffy.
04 -
Incorporate egg whites, one at a time, fully mixing after each addition, then blend in peppermint extract.
05 -
On low speed, alternate adding flour mixture and milk in three parts dry to two parts milk, mixing just until combined.
06 -
Stir in neon green food coloring until batter is uniformly tinted.
07 -
Transfer batter to prepared cookie sheet, spread evenly, and bake for 18 minutes or until a toothpick inserted in the center comes out clean.
08 -
Allow cake to cool completely, then crumble into fine crumbs and combine with enough green buttercream frosting to bind. Shape mixture into egg-sized balls.
09 -
Roll out chocolate fondant to desired thickness, use template to cut out shell shapes for each cake ball.
10 -
Enclose each cake ball with the fondant shell, closing some completely and leaving others partially open. Trim excess fondant at the base and smooth seams.
11 -
Using the piping bag with green royal icing, pipe onto the tops of each cake ball to create an alien slime effect.