Warm the milk gently. Add milk to a small saucepan over low to medium-low heat.
Warm until steaming but not boiling. Avoid scalding; you want gentle heat to preserve the milk’s sweetness.
Melt the white chocolate. Stir in the chopped white chocolate (or chips) and a pinch of salt. Whisk constantly until fully melted and smooth.
If needed, lower the heat to prevent scorching.
Add peppermint and vanilla. Stir in 1/8 teaspoon peppermint extract and a few drops of vanilla extract. Taste and add a bit more peppermint if needed. Go slow—too much can make the drink taste medicinal.
Brew the espresso. Pull 2 shots of espresso.
If you don’t have an espresso machine, use very strong brewed coffee or concentrated stovetop moka pot coffee.
Combine. Pour the espresso into a large mug. Slowly add the white chocolate milk mixture, stirring as you pour to blend everything evenly.
Finish and serve. Top with whipped cream if you like. Sprinkle crushed peppermint candies on top for a festive crunch and a little extra mint.
Adjust sweetness. If you prefer sweeter, stir in a bit more melted white chocolate or a teaspoon of simple syrup.
For less sweet, add a splash more milk or an extra shot of espresso.