Step 1: Preheat the Oven

1. Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan or line it with parchment paper.

Step 2: Prepare the Cake Batter

1. In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt until well combined.
2. Add the softened butter, condensed milk, milk, eggs, and vanilla extract. Beat on medium speed for about 2–3 minutes until the batter is smooth and well combined.

Step 3: Bake the Cake

1. Pour the batter into the prepared cake pan, spreading it evenly.
2. Bake in the preheated oven for 30–35 minutes, or until a toothpick inserted in the center comes out clean.
3. Remove from the oven and let the cake cool in the pan for about 10 minutes, then transfer to a wire rack to cool completely.

Step 4: Prepare the Ganache (Optional)

1. In a small saucepan, heat the heavy cream over medium heat until it just begins to simmer.
2. Remove from heat and add the chocolate chips. Let it sit for a minute, then stir until smooth and glossy.

Step 5: Assemble and Serve

1. Once the cake is completely cool, pour the chocolate ganache over the top, allowing it to drip down the sides.
2. Cut into slices and enjoy your chocolate cake.