Pour the Rice Chex cereal in a large bowl, set aside.
In a microwave safe bowl, melt the white chocolate by placing it in the microwave for 30 seconds to 1 minute, stirring every 20 seconds. The chocolate is ready when about half is fully melted. Continue to stir the chocolate in the bowl until the rest melts completely.
Pour melted chocolate over the cereal. Stir it all together gently. Stir in sprinkles gently while the chocolate is still warm.
In a large zipped top bag or covered container, add the protein powder. Pour the white chocolate covered cereal into the bag with the protein powder. Seal the bag or container and shake until all the cereal is coated with the protein powder. Enjoy!