Begin by measuring 6 cups of Rice Chex cereal and placing it in a large mixing bowl. Set this aside as your base.
In a microwave-safe bowl, combine 1 cup of semisweet chocolate chips along with 1/2 cup of white chocolate chips. Heat the mixture in the microwave for 30 seconds, then stir. Repeat this process until the chips are completely melted and the mixture is smooth—this should take about 1 to 2 minutes total.
Once melted, add 1 teaspoon of peppermint extract to the chocolate mixture. Stir well to ensure the peppermint flavor is evenly distributed throughout.
Carefully pour the melted chocolate mixture over the Rice Chex cereal. Using a spatula or wooden spoon, gently fold the cereal until every piece is thoroughly coated with the chocolate mixture.
Next, take a large zip-top bag and combine 1 cup of powdered sugar with 1 cup of crushed peppermint candies inside it. Close the bag securely to avoid spills.
Add the chocolate-coated Rice Chex cereal to the zip-top bag. Seal it tightly, then shake vigorously until all the cereal pieces are well-coated in the sugary peppermint mixture.
If desired, gently fold in 1/2 cup of mini marshmallows at this stage for an extra touch of sweetness and delightful texture.
Finally, spread the entire mixture out onto a baking sheet lined with parchment paper. Allow it to cool and set for about 30 minutes, letting the chocolate coating firm up.
Notes
For a charming festive display, serve in a colorful holiday bowl or package in individual treat bags tied with festive ribbons.