Preheat oven to 350 degrees F.
In a mixing bowl beat egg until become foamy.
Gradually add sugar to the egg and continue to beat.
Now add melted butter to the mixture and beat again for 2 mins.
Sift dry ingredients together including flour, baking powder, baking soda and salt.
Now gradually add dry mixture into the eggs, meanwhile add buttermilk to the mixture and mix all the ingredients together to make smooth batter.
Pour this batter into the greased baking loaf pan and place it in preheated oven for 60 mins. at 350 degrees F.