Preheat oven to 180°C (approximately 350°F).

Prepare water bath by fitting a round cake pan in a second, larger pan.

Fill the second pan with boiling water to create the water bath.

Drizzle caramel into the cake pan.

In a mixing bowl, beat sugar and eggs until light and fluffy.

Add melted butter and stir until well combined.

In a separate bowl, combine flour, cocoa powder, and baking powder.

Gradually add the dry ingredients to the wet ingredients, alternating with milk, and beat until smooth.

Pour the batter into the caramel-lined cake pan.

Mix all remaining ingredients (presumably for the pudding layer) and pour over the cake batter.

Pour boiling water into the larger pan to create the water bath around the cake pan.

Bake in the preheated oven for about an hour, or until a toothpick inserted into the center comes out clean.

Let the cake cool in the pan completely.

Once cooled, remove the cake from the pan.

For best results, chill the pudding cake overnight before serving.