Add the milk, chocolate chips, vanilla syrup, and cocoa powder to a small saucepan and heat over medium-low heat. Whisk frequently until the chocolate is melted and everything is well combined and smooth.
Remove the chocolate mixture from the heat and froth with a milk frother. Set aside.
Brew your espresso or coffee into a mug, then top with the frother chocolate milk. Top with whipped cream if desired, then drink up!