In a medium saucepan, combine the whole milk (or half-and-half), heavy cream, sugar, medium-ground coffee, and kosher salt. Heat over medium heat for 5–7 minutes until warm but not boiling.

Remove from heat and let steep for 15 minutes.

Whisk the large egg yolks and remaining sugar until pale and slightly thickened.

Gradually pour about half of the warm coffee mixture into the egg yolks while whisking continuously. Then whisk the egg mixture back into the saucepan with the remaining coffee base.

Return the saucepan to medium heat and cook, stirring for 5–8 minutes until thick enough to coat the back of a spatula.

Strain the custard through a fine-mesh sieve into a bowl set over an ice bath. Stir until cool.

Cover the bowl with plastic wrap and refrigerate for at least 4 hours, ideally overnight.

Transfer the custard to an ice cream maker and churn according to manufacturer’s instructions.

During the last few minutes of churning, drizzle in the cajeta and sprinkle in the chopped chocolate or handmade chocolate chips.

Transfer to an airtight container, layering additional cajeta and chocolate chips. Freeze for at least 4 hours.

Once frozen, scoop out and enjoy!