Preheat your oven to 170°C (325°F) and prepare the loaf tin by greasing it with butter or lining it with parchment paper.

In a large mixing bowl, cream together room temperature butter and granulated sugar until light and fluffy, about 3-5 minutes.

Gradually add beaten eggs to the mixture, mixing slowly for 2-3 minutes until smooth and pale.

Dissolve instant coffee in warm milk and mix it into the batter. Sift flour, baking powder, and salt separately, then combine with the wet mixture until just combined.

Pour the batter into the prepared loaf tin, smoothing the top with a spatula.

Bake in the preheated oven for 55-65 minutes or until a skewer inserted into the center comes out clean.

Once baked, cool in the tin for 10 minutes before transferring to a wire rack to cool completely.