I like Hershey’s unsweetened cocoa powder here, for its milk chocolate flavor, that perfectly balances out the bitterness of semisweet chocolate pieces, but you can use your favorite brand. I have not tested this cake with dutch processed cocoa.
Warming the milk in the microwave for about 40 seconds, avoids the risk of solidifying the melted butter once it hits the milk.
I prefer semisweet chocolate here, but you can use dark, milk, or a mix of both, if you prefer. In the pictures, I use Hershey’s semisweet baking chocolate bar, which I had brought along from a recent trip to Dubai and I love it. Chocolate chips may be used instead of bar chocolate.
For a less rich cake, feel free to omit the chocolate bar altogether. You’ll still get a saucy cake, if you’re careful not to overbake it. Chocolate pieces adds another layer of chocolate flavor which I love, but it’s not essential for achieving the pudding-like consistency of the cake.
I almost always bake this cake in an 8-inch square pyrex dish, but changed to a 7 X 10-inch ceramic dish this time around, because I found it more photogenic. I’ve noticed the glass dish bakes the cake in longer time than the ceramic one. The glass bakes in about 20 to 23 minutes, while ceramic baked in 15 to 17 minutes. So keep the material of your dish in mind when checking for doneness.