In a large mixing bowl, pour in the crispy rice cereal squares. Spread them out evenly.

In a microwave-safe bowl, combine the white chocolate chips and butter. Heat in 30-second bursts, stirring until smooth.

Stir in the lemon zest, lemon juice, vanilla extract, and optional yellow food coloring until well blended.

Pour the melted mixture over the prepared cereal and fold until every piece is coated.

Transfer the mixture into a resealable bag, add powdered sugar, and shake until fully coated.

Spread the mixture onto wax paper and let it cool for about 30 minutes until firm.