In a mixing bowl, beat butter with an electric mixer on low speed or by hand until creamy, then blend in egg. Slowly add dry organic cookie mix and blend until a dough forms.
Gather dough into a ball and flatten into a disc. Wrap dough in plastic and freeze 15 minutes or until firm. Preheat oven to 350 degrees and line a baking sheet with parchment paper. Remove dough from freezer.
Roll out on a floured, flat surface to 1/4” thick. Use the skull-shaped cookie cutter to cut the dough. Place cookies at least 2” apart onto prepared pan. Bake 13-15 minutes, until the edges begin to turn golden. Remove from oven and cool 5 minutes on cookie sheet before transferring to a wire rack to cool completely.
To make the frosting, in a large bowl using an electric hand blender, beat the butter and yogurt together until smooth. Add dry organic frosting mix and blend a minute more until smooth and creamy.
Divide frosting into as many colors as you desire to make. Add natural food dye and mix thoroughly to combine. Place colored frosting into piping bags and cut off the tips. Use the different colors to create your own Day of the Dead cookie designs! Enjoy immediately.