Preheat your oven to 180°C (350°F).

In a small bowl, combine 2 tablespoons of instant coffee with 4 tablespoons of water, stirring until the coffee granules are fully dissolved.

In a large mixing bowl, cream together 225 g of unsalted butter and 225 g of sugar using an electric mixer until light and fluffy.

Add the 4 large eggs one at a time, beating well after each addition.

Stir in the dissolved coffee and 1 teaspoon of vanilla extract into the batter.

In a separate bowl, sift together 225 g of all-purpose flour and 1 teaspoon of baking powder.

Gradually add this flour mixture to the wet ingredients, mixing gently until just combined.

Fold in 100 g of chopped walnuts carefully.

Grease a loaf pan and pour the prepared mixture into it.

Bake for 45-50 minutes, checking for doneness with a toothpick.

Allow the loaf to cool in the pan for about 10 minutes before transferring to a wire rack.