Heat the whole milk, chocolate syrup, and cocoa powder together in the microwave or on the stove top until hot. Whisk well to combine.
Pour the milk into a mug along with the coffee. Stir in the peppermint syrup to taste.
Top with whipped cream and serve hot.
Notes
Milk: We prefer whole milk, but any variety of dairy or nondairy milk will work fine here. Oatmilk is very creamy and delicious in this latte.Variations: For a less sweet version, leave out the chocolate syrup. For a sweeter version, add more chocolate syrup or stir in simple syrup to taste.Separation: Cocoa powder doesn't dissolve very well into hot liquids, so it may separate a bit the longer it sets and cools. Just stir to combine again and you're good to go.Iced Peppermint Mocha: Whisk the chocolate syrup and cocoa powder together with very hot coffee or espresso to combine. Pour over ice and top with milk and peppermint syrup. Stir to combine.