1 1/2 cup milk
1 1/2 cups heavy cream
3/4 cup sugar
1/2 cup roughly chopped graham crackers
4 ounces bittersweet chocolate, chopped
Over medium heat, warm the milksugar and salt in a medium sauce pan, stirring frequently until the sugar has dissolved. Remove from heat and stir in the crackers. Steep the crackers until they have dissolved, about 3 minutes.
Strain the mixture through a sieve and add the cream. Chill the base until cold. This can be done either in the fridge for a few hours, or more quickly, by pouring the ice cream base into a ziplock bag, sealing tightly and submerging in ice water for about 30 minutes.
Once cold, churn the mixture in an ice cream maker according to manufacturer directions. Stir in the chocolate chunks, pour in to a container, and freeze ice cream until firm.