Make cupcakes and frost them with red icing. For the spots, add brown M&Ms.
Caterpillar Cake
Place cupcakes in a wriggly line on a tray and stick them together with icing. Use licorice sticks for the antennae and candies for legs, mouth and eyes.
Ladybug Watermelon
Slices of watermelon, with the seeds rearranged to form spots, can also liven up the table.
You can also serve raspberry ice cream with chocolate chips on top.