How to Make It
Place melting wafers and chopped chocolate in a microwave-safe bowl. Microwave at 50% power 30 seconds, and stir. If not melted, microwave in 15-second intervals, stirring until melted and smooth.
Spread mixture evenly on a 15- x 10-inch jelly roll pan lined with parchment paper. Top evenly with pistachios; sprinkle with rose petals, and gently press to adhere. Chill until set, about 30 minutes. Break into pieces.