When I made these eyeball cupcakes, I just placed the gummi candies right on top of the veiny cupcakes. Unfortunately, it didn't occur to me that the red from the vein frosting would show through the translucent gummis and they ended up looking more brown than green. Below, I included instructions to spread a small amount of white frosting on the bottom of each gummi so the red veins won't be visible.
Quick Note: If you can't find Lifesaver Gummis, you can just use regular Lifesavers. Adhere the Mini M&Ms with a tiny bit of frosting. I went with the gummis because these cupcakes were for toddlers and preschoolers and I feared the Lifesavers could be a choking hazard.
1 box white cake mix (enough to make 24 cupcakes)
1 small box lime Jell-o powder
1 can white frosting
1 squeeze pouch red frosting (or you can add lots of red gel food coloring to additional white frosting)
1 package Lifesaver Gummis (one package had 27 green candies, you can always make different colored eyes if you run out of green)
24 brown Mini M&Ms (you can buy these in either a large bag or small tubes, two tubes had enough brown candies)
Preheat oven and prepare cake mix according to package directions, adding the box of Jell-o powder to the mix. Bake in 24 cupcake papers according to box directions. Cool completely.
Set aside about 3 tablespoons of the white frosting, then frost the cupcakes with the remaining frosting. Pipe red frosting over the cupcakes to look like veins.
Place one Mini M&M into the center of each green Lifesaver Gummi, it should be a perfect fit. I did it so the M and Lifesaver logo were facing the same direction.
One at a time, spread a small amount of white frosting over the bottom of the Lifesaver Gummi (do this on the side with the M and the Lifesaver logo), then immediately place frosting side down on the center of a cupcake. Repeat with remaining candies and cupcakes.
Yield: 24 cupcakes