On large round platter or pizza pan, arrange cupcakes, placing them close together. In medium bowl, mix food colour and frosting. Spread frosting over cupcakes and spaces in between to create 1 large circle of frosting. Squeeze 1 large dot of black gel in centre of frosting. With gel, draw concentric circles around the dot, spacing them about 2 inches apart. To create the web design, drag a toothpick from the centre dot to the outer edge of the circle, about 12 times. Place plastic spiders on web. Store loosely covered.