Step 1: Preheat the oven

• Preheat your oven to 180°C (350°F). Grease and line a 23cm cake tin with parchment paper.

Step 2: Mix the dry ingredients

• In a large mixing bowl, sift together the plain flour, caster sugar, cocoa powder, and baking powder.

Step 3: Combine the wet ingredients

• In a separate bowl, whisk together the melted butter, cola, milk, eggs, and vanilla extract.

Step 4: Make the batter

• Gradually add the wet ingredients to the dry ingredients, stirring until just combined. Avoid overmixing to ensure a light texture.

Step 5: Bake the cake

• Pour the batter into the prepared cake tin.
• Bake in the preheated oven for 35–40 minutes, or until a skewer inserted into the center comes out clean.

Step 6: Cool the cake

• Allow the cake to cool in the tin for 10 minutes before transferring it to a wire rack to cool completely.

Step 7: Prepare the glaze

• Melt the dark chocolate and butter together in a heatproof bowl over a pan of simmering water.
• Remove from heat and stir in the icing sugar and cola until smooth and glossy.

Step 8: Glaze the cake

• Pour the chocolate glaze over the cooled cake, allowing it to drip down the sides. Smooth with a spatula if needed.

Step 9: Serve

• Let the glaze set for a few minutes, then slice and serve.