Preheat your oven to 300°F (150°C) and gather four ramekins. Place them in a deep baking pan with space between each.

Bring a kettle of water to a boil for the water bath.

In a medium saucepan, combine 2 cups of heavy cream, 1/4 cup of granulated sugar, and a pinch of kosher salt over medium heat. Stir until sugar dissolves and mixture is hot.

In a large bowl, whisk together 6 egg yolks until smooth. Gradually pour warm cream mixture into yolks while whisking to prevent curdling.

Mix 2 tablespoons of instant espresso powder with 2 tablespoons of Kahlúa until dissolved. Stir this into the custard and strain through a fine mesh sieve.

Pour the custard into ramekins and add boiling water to the baking pan halfway up the sides of the ramekins. Bake for 25-35 minutes until edges are set but centers jiggle slightly.

Remove from water bath and cool for about 30 minutes. Refrigerate for at least 4 hours or up to 2 days.

Before serving, sprinkle an even layer of sugar on each custard and use a kitchen torch to caramelize until golden brown.