Mix pudding according to instructions on package. Add a few drops of green food coloring to the vanilla bowl, until desired shade is achieved.
Scoop about ½ cup of vanilla/green pudding into the bottom of 8 cups.
Before scooping the chocolate pudding, reserve ¼ cup aside to later use for decorating the mouth. Then scoop about ¼ cup of chocolate pudding onto the top of each cup. The goal is to have a ratio of ⅔ of green pudding and ⅓ of chocolate pudding.
Insert a lollipop stick into the center of each one and place cups on baking sheet for easy transport to the freezer. Freeze for about 5 hours, or until firm.
Once completely frozen, peel off paper cups.
Place the ¼ cup of reserved chocolate pudding in a piping bag (or plastic bag with tip cut off) and pipe on the stitched mouth. To place eyeballs, pipe a small dot of pudding onto the back of each one and press on.
Serve immediately or place in freezer for 10-15 minutes for the eyeballs and mouth to freeze.