STEP 1: Make Cake Pop Filling, Paint Candy Coating in Molds
Bake and cool the red velvet cake per the box instructions. Crumble the red velvet cake into a bowl until there are no large chunks of cake left and the texture is only crumbs. (Using your hands generally makes this easier) Mix in 1/3 - 1/2 tub of icing using a rubber spatula or spoon. The mixture should just hold together when squeezed but not be too squishy. Add additional icing as necessary. Refrigerate the filling.
Next, melt the black and green candy coating discs in the microwave on 50% power, stirring frequently until just melted (the black will be thicker than the green). Then, add a pinch or two of paramount crystals to the black coating and stir until you have a more fluid consistency for painting (This step is necessary or the black will be too thick to paint).
Use a paintbrush to dab a thick layer of black coating on the eyes, nose and mouth of each skull mold, taking time to cover the areas thorougly. Place the mold in the fridge for 5 minutes.
Remove the mold from the fridge and then paint a thick layer of green on the entire inside of each cavity, creating a shell. Place the mold back into the fridge for 5 minutes to harden. Remove, hold up to the light, and touch up any areas that seem thin.
STEP 2: Fill Mold, Add Stick, Seal
Press a small amount of red velvet filling into each mold, leaving a 1/8" gap for sealing.
Dip each sucker stick end in melted coating and press firmly into the mold, adhering to the cake.
Use additional melted green coating to completely seal the back of each skull pop. Place the mold in the freezer for 15 minutes.
STEP 3: Finish
Remove the mold from the freezer and gently pop each cake pop out. Let them sit and come to room temperature again.Use the craft knife to cut and crack off a portion of each skull, revealing the red velvet "brains".
Pack some excess "brains" on top to enhance.
Attach the yellow candies using additonal melted coating and use a food coloring marker to draw in each pupil.