As seen on Pennies on a Platter

1 1/2 cups whole milk
3/4 cup sugar
1 1/2 cups whole coffee beans
pinch of salt
1 1/2 cups heavy cream, divided
5 large eggs yolks
1/4 teaspoon vanilla extract
1/4 teaspoon finely ground coffee

Pour 1 cup of the cream into a large bowl; set aside. Whisk together the egg yolks in a separate medium bowl; set aside.

Using a medium saucepan, heat the milk, sugar, whole coffee beans, salt and the remaining 1/2 cup of the cream until warm. Cover, remove from heat and let steep at room temperature for 1 hour.

Rewarm the mixture then slowly pour into the egg yolks, whisking constantly. Scrape back into the saucepan.

Heat over medium heat while stirring constantly with a heatproof spatula, until the mixture thickens and coats the spatula (about 10 minutes). Pour the custard into the 1 cup cream through a mesh strainer and stir. Press on the coffee beans to extract as much of the coffee flavor as possible, then discard the beans.  Stir in the vanilla and the ground coffee, stirring until cool over an ice bath.

Chill the mixture thoroughly in the refrigerator, then freeze in your ice cream maker according to the manufacturer's directions.

Source: Adapted from The Perfect Scoop, by David Lebovitz

http://penniesonaplatter.com/2010/03/02/coffee-ice-cream/