In a pot on stovetop, combine ½ cup cashew butter, brown rice syrup, vanilla extract, 1 teaspoon peppermint extract and powdered sugar. Whisk over medium-low heat until smooth.
Pour cashew butter/brown rice syrup mixture over the cereal in a large bowl and mix well so that every bit of cereal is covered.
Spread out in an 8x8 baking pan lined with parchment (make the parchment long enough so you have "handles" to lift out the whole square of bars once they are done).
Put pan in fridge for 30 minutes to set.
For the Chocolate Peppermint Ganache Topping: Combine 1 cup chocolate chips, almond milk and 1 tsp peppermint extract in a pot on the stove. Whisk until smooth. If the ganache is too thick, add more milk 1 tbsp at a time until desired consistency is reached.
Take cereal bars out of fridge and pour the ganache on top, spreading it out evenly over the bars.
Put back in fridge for at least another 30 minutes until ganache topping is set. Sprinkle crushed peppermint candy canes over the top.