In a small bowl, mix ¼ cup of the butter with ¼ cup of the buttermilk. Set aside. Combine flour, sugar, baking soda, baking powder, salt and ½ cup of the butter in a large mixing bowl. Add the egg and one cup of the buttermilk and mix well. Remove dough from bowl and gently knead on a lightly floured surface. Form dough into a ball and place onto a buttered baking sheet. Brush dough with butter previously set aside and cut a large X into the top.
Bake in a preheated oven at 375°F for 50 minutes or until a toothpick inserted into the center comes out clean, brushing at least once more with the buttermilk mixture while baking and turning the loaf upside for the last 10 minutes. Place on a cooling rack, cover with a towel and let stand for 10 minutes before serving.
Serve warm with butter.