In a medium saucepan, whisk the milk, heavy cream, espresso powder, and salt together. Heat over medium until it’s steaming and almost simmering, don’t let it boil.
1 ½ cups heavy cream, 1 ½ cups whole milk, 3 tablespoon instant espresso powder, Pinch salt
In a separate bowl, whisk the egg yolks and sugar together until the mixture looks pale and slightly thickened. Slowly pour in about half of the hot cream while whisking constantly, this helps gently warm the yolks so they don’t scramble. Then, whisk the tempered yolks back into the saucepan with the rest of the cream.
¾ cup granulated sugar, 4 large egg yolks
Keep cooking over medium-low heat, stirring constantly with a wooden spoon or heatproof spatula, until the mixture thickens a bit and coats the back of your spoon—like a thin custard. It should reach about 170–175°F (77–80°C), but don’t let it boil.
Take the pan off the heat and pour the mixture through a fine mesh sieve into a clean bowl to catch any bits. Stir in the vanilla extract, let it cool for a bit, then cover and chill in the fridge for at least 4 hours, or overnight if you’ve got the time.
1 teaspoon vanilla extract
Once it’s fully chilled, pour the custard into your ice cream maker and churn it following the machine’s instructions, usually about 20–25 minutes until it’s softer and more thick, like soft serve.
Scoop the churned ice cream into an airtight container. Press parchment or plastic wrap right on the surface to keep it smooth and ice-crystal free. Freeze for at least 4 hours until it’s firm and scoopable.