- 2 tablespoons unsalted butter
- 1 slice brioche or Pullman bread, cut crosswise into 3/4-inch square strips
- 1/4 cup raw sugar
- 1 pinch kosher salt
- 1 cup whole milk
- 2 tablespoons heavy cream
- 1 1/2 ounces bittersweet chocolate (at least 70% cacao), finely chopped
- 1 1/2 ounces milk chocolate, finely chopped
- 1 tablespoon cornstarch
- 2 tablespoons unsweetened cocoa powder, plus more for serving
- 1 single shot espresso (about 1 ounce)
- 1 tablespoon sugar
- 1 pinch kosher salt
- 1 1/2 ounces amaro (preferably Nonino)
- Whipped cream (for serving)
- Heat butter in a small skillet, preferably nonstick, over medium-low until it begins to foam. Add brioche and cook, turning occasionally, until golden brown on all sides, about 3 minutes total. Transfer to paper towels and let drain.
- Wipe out skillet and sprinkle with sugar and salt; set over medium heat. Cook (undisturbed) until edges of sugar begin to melt, about 1 minute. Stir sugar, bringing edges in toward the center to prevent burned spots, and continue cooking until all sugar is melted and turns amber color, about 4 minutes. Add brioche and quickly turn to coat all sides in caramel, about 30 seconds. Transfer to a parchment-lined rimmed baking sheet and let cool.
- Combine milk and cream in a 2-cup measuring glass. Pour 1/4 cup milk mixture into a small saucepan and add bittersweet chocolate and milk chocolate. Heat over medium-low, stirring occasionally, until chocolate is melted, about 2 minutes. Reserve remaining milk mixture.
- Meanwhile, whisk cornstarch and 2 Tbsp. cocoa powder in a small bowl. Whisk in 1/4 cup reserved milk mixture, then whisk in remaining milk mixture.
- When chocolate is melted, add cocoa mixture, espresso, sugar, and salt and cook, stirring often, until liquid begins to boil and thicken, about 4 minutes. Remove from heat and add amaro.
- Divide mocha among mugs. Top with whipped cream and dust with cocoa powder. Serve with caramelized brioche.