Delicious. Yields 4 half-cup servings.

High quality chocolate chips a la Guittard will work in this recipe. Cheap chocolate chips won't melt appropriately; you'll want to finely chop a bar.

Ingredients Step
65 g (⅓ c.) sugar
30 g (⅓ c.) cocoa
2 T. cornstarch
⅛ t. salt
In a saucepan, stir together.
2 c. milk Slowly stir in, stirring until smooth and combined.
Heat mixture over medium-low head, stirring constantly, until the pudding thickens. It will bubble and coat the back of the spoon (about 5-10 minutes).
3-4 oz. (85-115 g) chocolate, finely chopped Add and stir vigorously, until the pudding is very thick and smooth (about 30 seconds).
1 t. vanilla Remove from heat. Stir in vanilla.
Pour into ramekins. Cover each ramekin to avoid forming a skin (possibly with plastic wrap).

Source: Ali Slagle (NYT Cooking)