Prepare the boxed cake mix by the instructions on the box for cupcakes preheat oven to 350-degrees. Spoon into lined cupcake pan. Bake until a toothpick comes out clean.
Cool cupcakes completely before decorating.
Break marshmallow fondant into ¼ and ¾ portions. Work 15-20 drops of yellow GEL food coloring into a larger portion of marshmallow fondant.
Break yellow marshmallow fondant into 12 smaller pieces. Further, break each of these smaller pieces up into 24 randomly-sized pieces.
Form each of these 24 small pieces into a thin, long cylinder that you then smash flat. This is a petal. With the remainder ¼ of the marshmallow fondant, work in 5-10 drops of black food coloring.
Break this black fondant into 12 equal-sized pieces and roll each one into a ball. Make each black ball into a flattened circle and add texture by poking with a butter knife edge or your fingernail. These are the centers of your sunflowers.
Place parts of your sunflowers into the refrigerator until you’re ready for them. With your largest decorating tip, press into the top of the cupcake off-center, creating a well. Save hole tops.
Place 1 tablespoon of the blue sanding sugar sprinkles inside the well in the cupcake.
Replace hole top on each cupcake.
Mix 4-5 drops of blue food coloring into your vanilla frosting, stirring until the color is consistent.
Place star tip in piping bag.
Fill the piping bag with the blue frosting.
Frost each cupcake in a swirl, turning the piping bag as you pipe.
Starting with your largest petals, lay 24 petals in an overlapping circle on one side of a cupcake.
Place a sunflower center in the middle of the petals.
Repeat with all 12 cupcakes. Serve up for a garden party or Frozen Birthday party - Enjoy!