• Place the chocolate chips in a large bowl and melt over a double boiler until all the chocolate has melted. You can also melt it in 30 sec. intervals in the microwave, making sure to stir between each interval.
• Pour popped amaranth into the bowl with the chocolate and mix well. with a wooden spoon, to incorporate.
• Wet the mold a little bit with a moistened paper towel and press the amaranth chocolate mix into the mold. 
• Press the cardboard square against the mold and flip the mold, to have the skull facing you. Lift the mold, and carefully place the cardboard with the skull on it on a sheet tray.
• Repeat this process with the rest of the mix. Let chocolate set for 30 min.

Royal Icing

• While de chocolate is setting, in a large bowl, lightly beat the aquafaba until it starts to bubble. Add 4 cups of the powdered sugar and mix well. Test the consistency of the icing on a plate. It should be thick enough that it doesn’t slide down the plate easily. If it seems too thin, add 1 more cup of powdered sugar. The consistency should be considerably thicker than the icing used to decorate cookies.
• Separate the icing into 4 small bowls. Add your food coloring of choice and mix well.
• Pour each bowl of icing into a disposable piping bag. Secure with a rubber band, and cut a tiny bit off of the tip of the bag. Test the amount of icing that comes out before decorating your skull.
• Decorate your skull however you desire. The icing will take about 30 min. to set.