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.
Spread melted chocolate onto rice cake evenly with back of spoon. Place on rack.
If desired, top rice cakes with chopped nuts, fruits, seeds, etc., pressing gently into chocolate.
Move to the refrigerator for the chocolate to harden completely.
Store rice cakes in an airtight container in the fridge.
Notes
You can also melt the chocolate using the double-boiler method.
If using the microwave to melt the chocolate chips, using a shallow bowl where the chips are mostly in one layer yields the best results.
You can also dip the rice cake into the melted chocolate, but you will still end up having to spread the chocolate with a spatula or back of a spoon to even it out.
I like using dark chocolate chips, but try it with different chocolates: milk, semi-sweet, mint, etc.
Do a swirl of two different chocolates!
Top with chopped nuts, seeds, dried fruit, sea salt, pomegranate seeds, etc.