To begin, preheat your oven to 350°F (175°C). While the oven is heating, grease a 9-inch round cake pan or line it with parchment paper for easier removal. Preparing your ingredients and tools in advance helps make the baking process smoother.

First, combine the melted butter, granulated sugar, and brown sugar in a large mixing bowl until smooth. Then, add the eggs one at a time, mixing thoroughly after each addition to create a glossy batter. Afterward, stir in the vanilla extract to enhance the chocolate’s depth.

In another bowl, combine the flour, cocoa powder, salt, and baking powder by whisking them together. Next, gradually add the dry ingredients to the wet mixture, stirring gently until just combined. Finally, fold in the chocolate chips or chunks to add texture and richness.

Once the batter is prepared, pour it into the greased pan, spreading it evenly with a spatula. Bake for 30-35 minutes, or until a toothpick inserted in the center emerges with a few moist crumbs attached. Be careful not to overbake, as this will ensure that the center remains soft and fudgy.

Once you take the cake out of the oven, allow it to cool in the pan for 10-15 minutes. Afterward, move it to a wire rack to cool down fully. This cooling step is essential for setting the cake’s structure, making it easier to frost or decorate without crumbling.