Pipe on round mound of frosting on each cupcake with a large round tip and a pastry bag, or just use a spoon. Wilton's cupcake decorating kit has large tips perfect for this!
Place two miniature chocolate chips for eyes.
Place one pink sprinkle or miniature jelly bean for the nose.
Make whiskers using the long skinny sprinkles in the color of your choice. If you don't have sprinkles, broken spaghetti works too!
Cut marshmallow in half at an angle. Dip the cut sides in sanding sugar and place on top of the cupcake to make the rabbit's ears.