Preheat the oven to 180°C (350°F).
Grease and line a loaf tin with baking parchment.
In a large mixing bowl, beat together the softened butter and golden caster sugar until light and fluffy.
Add the eggs one at a time, mixing well after each addition.
Stir in the cooled brewed coffee and vanilla extract until combined.
Sift the self-raising flour and salt into the mixture, then fold gently until just combined.
Fold in the chopped walnuts.
Pour the batter into the prepared loaf tin and smooth the top.
Bake for 50–60 minutes, or until a skewer inserted comes out clean.
Allow the cake to cool in the tin for 10 minutes, then transfer to a wire rack.
Once cool, slice and serve as desired.
