Preheat oven to 350°F. Grease a standard loaf pan.
In a large bowl, mix sugar, butter, milk, egg, and maple flavoring until smooth.
In a separate bowl, combine flour, baking powder, and salt.
Gradually add dry ingredients to the wet mixture, stirring just until combined.
Fold in the chopped nuts.
Pour batter into the prepared loaf pan and spread evenly.
Bake for 50-60 minutes, or until a toothpick inserted in the center comes out clean.
Cool in the pan for 10 minutes, then remove and let cool completely on a wire rack.