Rich Chocolate Ice Cream

Or, Carob Ice Cream, which I plan on making.  This is a custard-type ice cream, which gives it richness.

8 squares (8 oz.) bittersweet chocolate, chopped (or use 8 oz. carob chips)
2 cups half-and-half or whole milk
3 egg yolks
1/4 cup granulated sugar
1 1/2 cups heavy whipping cream
1 tablespoon vanilla extract

1. In a saucepan over low heat, melt chocolate (or carob chips) with 1/2 cup half-and-half, stirring frequently until smooth.  Remove from heat.
2. In a saucepan over medium heat, bring remaining half-and-half to a boil.  In a bowl with hand-held mixer, beat egg yolks and sugar until thick and creamy, 2 to 3 minutes.  Gradually pour hot milk over yolks, beating constantly, then return mixture to saucepan.
3. Cook over medium heat until custard thickens and lightly coats the back of a spoon, stirring constantly until well blended.
4. Pour cold cream into a bowl and strain custard into bowl with cream.  Blend well and cool to room temperature.  Refrigerate until cold.
5. Transfer custard to an ice-cream maker and freeze according to manufacturer's directions.  Leave to soften 15 to 20 minutes before serving.