01 -
In a medium saucepan, mix together the granulated sugar, cocoa powder, and heavy cream until fully combined.
02 -
Place the saucepan over medium heat, stirring continuously to prevent burning, and bring the mixture to a boil.
03 -
Remove the pan from heat, then add the unsalted butter and vanilla extract, stirring until the mixture is smooth and fully melted.
04 -
Fold in the chocolate chips and optional chopped walnuts while the mixture is still warm, ensuring even distribution.
05 -
Transfer the mixture into a greased 20 cm square pan, spreading evenly, then allow it to cool at room temperature until fully set.
06 -
Once set, cut into 24 squares and serve as a rich chocolate treat.