°1 cup sugar
°½ cup cocoa powder
°1 cup all-purpose flour
°2 teaspoons yeast
°Half a teaspoon of salt
°°Half a cup of milk
°4 tablespoons melted butter
°1 large egg yolk
° 2 t of vanilla extract
°Half-sweet chocolate chip cup
°1 c boil water

* Methods :

1- Preheat oven to 350 degrees F. Spray an 8-inch square bowl with cooking spray. Whisk ½ c sugar with ½ c cocoa powder also set aside.
2- Whisk the flour, the remaining cup of sugar, a cup of cocoa, baking powder and salt in a large bowl. Whisk the milk, butter, egg yolks, and vanilla in a medium bowl until smooth. Stir the milk mixture into the flour mixture until completely combined. Stir in the chocolate chips (the mixture will be stiff).
3- Using a rubber spatula, scrape the mixture into the prepared pan and spread it into the corners. Sprinkle the cocoa mixture and reserved sugar evenly on top. Gently pour boiling water over cocoa. Don't move.
4- Bake until the top of the cake is cracked, the sauce is bubbling, and a toothpick inserted into the area of ​​the cake comes out almost clean, about 22 to 24 minutes.  Let it cool on a wire rack for at least 10 minutes. Serve hot with vanilla ice cream.

Enjoy !