As the kids say—YOLO.
Whisk together chocolate milk, water, powdered sugar, cocoa, and salt in a small saucepan over medium-high; bring mixture to a boil. Remove from heat; stir in potato flakes. Add 1 to 2 tablespoons of water, if needed, for desired consistency. Chill 1 hour. Serve with chocolate syrup, if desired.
God will judge you harshly for this