*This recipe was designed for an old-fashioned ice cream churn with a large capacity. If using a new 1 1/2 to 2 quart capacity ice cream maker, cut recipe in thirds.3 cups whipping cream
3 cups whole milk
9 egg yolks
1 1/2 cups sugar
1 tsp raspberry extract
1 tsp vanilla extract
food coloring, optional
1 1/2 cups chocolate chips
3 tsp oil
Combine milk and 1 1/2 cups cream in large saucepan over medium heat. Heat through, until bubbles form at the edges but do not boil. Meanwhile, Combine egg yolks, sugar and remaining cream. Whisk well until sugar begins to dissolve. When milk is heated through, slowly pour 1 cup hot milk mixture into egg yolk mixture, whisking vigorously while doing so. Yolk mixture should be warm now. Very slowly (about 1/4 cup at a time) whisk yolk mixture into remaining cream in saucepan, whisking continually. Be careful not to add to quickly, or egg will cook upon impact. When fully incorporated, turn on heat to medium low. Cook, stirring continually, until mixture thickens. Custard should coat back of spoon. When you see the first bubble or two, remove from heat. Do not boil.
After removing from heat, stir in vanilla and raspberry extract. Optionally, strain mixture to remove any possibility of cooked egg, but the mixture should have turned out pretty smooth. Transfer to large bowl. Let cool at room temperature for about 20 minutes, stirring occasionally. Cover with plastic wrap, touching surface of custard with plastic wrap to prevent film from forming on custard. Refrigerate at least 3 hours. Freeze in ice cream maker according to manufacturer's instructions.
Once ice cream has begun churning, melt chocolate chips and oil together in glass measuring cup. (Microwave 30 seconds, stir, microwave additional 30 seconds.) Stir until smooth. Allow to cool while freezing ice cream.
About 5 minutes before freezing is complete, (approximately 20 minutes after start time) add chocolate mixture to ice cream by pouring in while ice cream is churning. Allow to churn 3-5 minutes, until chunks form. Transfer ice cream to plastic container, cover and freeze 3 hours before serving.