Soften butter at room temperature and mix it until smooth. Gradually add sugar in three portions, mixing well after each addition.

Beat the eggs and add them gradually to the butter mixture, mixing thoroughly after each addition.

Sift the dry ingredients (cake flour and baking powder) and add them to the wet mixture. Sift again while adding to ensure no lumps.

Add milk to the batter and mix until combined.

Finally, add the coffee extract and mix well.

Grease a pound cake pan with melted butter, then pour the batter into the pan. Bake in a preheated oven at 170°C (340°F) for 45–50 minutes.