Preheat your oven to 375°F (190°C) and prepare your baking pan by greasing or lining it.

Melt the unsalted butter in a saucepan over low heat, then stir in the espresso powder until dissolved.

Mash the ripe bananas in a mixing bowl until smooth.

Combine the melted butter and espresso mixture with the mashed bananas.

Stir in granulated sugar and brown sugar until dissolved.

Add one beaten egg and mix well.

In a separate bowl, whisk together flour, baking soda, and salt, then add to the wet mixture.

Fold in the grated semi-sweet chocolate.

Pour the batter into the prepared loaf pan and smooth the top.

Bake for 40-45 minutes or until a toothpick comes out clean from the center.

Prepare coffee butter while baking by mixing softened butter, caster sugar, espresso grounds, cinnamon, and salt.

Cool the bread in the pan for 10 minutes before transferring to a wire rack to cool completely.