1 cup half-and-half
2 cups cream
¾ cup sugar
6 tablespoons whole coffee beans
6 egg yolks
1 to 2 teaspoons vanilla extract
Warm the half-and-half, cream sugar and coffee beans in a non-corroding saucepan to below the simmer. Keep warm or reheat the mixture from time to time for 30 to 45 minutes until it has the coffee flavor you want. Do not allow to boil.
Whisk the egg yolks to break them up, then stir in some of the warm mixture to temper the yolks. Return to the saucepan and cook over low heat, stirring constantly, until the mixture coats the spoon, about 165°F.
Strain into a bowl set over ice and let cool. Flavor with vanilla and chill in the refrigerator. Freeze according to the instructions with your ice cream maker.