1/2 cup butter, softened
2 eggs
1/4 cup white sugar
1 teaspoon vanilla extract
3 cups all-purpose flour
3 teaspoons baking powder
3/4 teaspoon salt
1 1/2 cups milk
4 egg whites
Preheat oven to 350 degrees F (175 degrees C). Grease a 9x5 inch loaf pan.
In a large bowl, cream together the butter, eggs, sugar, vanilla extract and flour. Beat in the milk, mixing just until incorporated. Spoon mixture into the prepared pan.
Bake at 350 degrees F (175 degrees C) for 1 hour. Cool completely before cutting into bars.