Take a non-stick pan as broad as possible and heat on medium flame.
Now, combine the Butter and chopped Dark Chocolates.
Let it cook for about 2 minutes, and make sure to stir continuously.
Once done, transfer the mix into a bowl to let it cool.
Then, add the Condensed Milk and Vanilla Essence in the same bowl.
Mix it all well, and once done, add the Maida Flour, Baking Powder, and Baking Soda.
Repeat the mixing process, and when you’re satisfied, add the Walnuts.
Now, take some muffin molds and put the mixture on them in equally distributed portions.
Next, put one cube of Dark Chocolate on each mold and slightly push in.
Set a temperature of 180°C (360°F) in your oven and bake them for about 15 minutes.
Finally, bring the muffins out of the molds and serve hot with some chocolate sauce.