3 large egg yolks, lightly beaten
3 cups skim milk
2/3 cup sugar
1/4 cup cornstarch
3 tablespoons unsweetened dark cocoa
1/8 teaspoon salt
1/2 teaspoon vanilla extract
2 ounces dark chocolate chips
Place egg yolks into a medium bowl and beat lightly; set aside.
In a heavy saucepan, heat milk over medium-high heat until tiny bubbles form around the edges. Immediately remove from heat and pour into a large mixing bowl. Pour the milk back into the saucepan and add sugar, cornstarch, dark cocoa powder and salt. Bring to a boil over medium heat and stir constantly to ensure a smooth texture.
When the mixture thickens, remove it from the heat and remove a cup of the mixture and whisk it into the egg yolks slowly to make sure the yolks don’t cook. Pour the egg yolk and chocolate mixture back into the saucepan with the rest of the chocolate mixture.
Return the pan to the stove and bring to a boil over medium heat, whisking constantly. When the pudding becomes thick, remove it from the heat and stir in the vanilla and dark chocolate chips. Stir to combine. Serve immediately or transfer the pudding to a serving bowl.