Note: Make sure to freeze the base of your ice cream maker overnight before making this recipe.

1. In a medium saucepan, slowly whisk the cornstarch into 1 cup cold whole milk, then whisk in the sugar and instant espresso. Apply medium heat and heat for 4 to 6 minutes, whisking frequently, until nearly simmering and the mixture thickens.
2. Remove from the heat. Stir in the remaining 1/2 cup whole milk, heavy cream, salt, and vanilla extract. 
3. Transfer the mixture to a large metal or glass bowl. Place the bowl in a smaller bowl of ice water for 1 hour, making sure not to splash any water into the ice cream. Alternatively, simply place the bowl in the refrigerator and wait for 3 to 4 hours or until the temperature drops to 40 degrees Fahrenheit.
4. Churn according to your ice cream maker instructions, about 25 minutes for soft serve consistency.
5. Transfer the churned ice cream into a loaf pan or storage container. Place the container in the freezer and freeze for at least 2 hours (or overnight), which “ripens” the ice cream and creates the hard ice cream texture. Store in a loaf pan with a parchment sheet over the top or a sealed container in the freezer for up to 2 weeks.