Preheat oven 350 degrees F (180 C). Place rice cakes on rack and toast in the oven for 5 minutes to crisp up. Let cool completely. Melt chocolate chips in microwave-safe bowl for 1 minute. Stir. Microwave at 15 second intervals until chocolate chips are completely melted, stirring after each 15 seconds. Dip one side of rice cake in the melted chocolate. (Alternatively, spoon the melted the chocolate onto the rice cake.) Spread evenly with back of spoon. Place on rack. If topping with nuts or dried fruit, sprinkle over the chocolate coated rice cake and press in gently. Let rice cakes rest until chocolate has cooled completely as beginning to harden, about 30 minutes. Move to the refrigerator for the chocolate to harden. Store in an airtight container at room temperature or in the fridge (depending on how hard you like your chocolate).