Tristan's Fantastic Irish Soda Bread

3	cups all-purpose flour
1	cup cake flour
1 1/2	teaspoons baking soda
1 1/2	teaspoons cream of tartar
1 1/2	teaspoons salt
2	tablespoons sugar
2	tablespoons unsalted butter , softened
1 1/2	cups low-fat buttermilk
1	tablespoon melted butter , optional

1. Heat the oven to 400 degrees and adjust a rack to the center position. Place the flours, soda, cream of tartar, salt and sugar in a large mixing bowl. Add the butter and rub it into the flour using your fingers until it is completely incorporated and the mixture resembles coarse crumbs. Make a well in the center and add the buttermilk. Work the liquid into the flour mixture using a fork until the dough comes together in large clumps. Turn the dough onto a work surface and knead briefly until the loose flour is just moistened. The dough will still be scrappy and uneven.

2. Form the dough into a round about 6 to 7 inches in diameter and place in a cast iron skillet. Score a deep cross on top of the loaf and place in the heated oven. Bake until nicely browned and a tested comes out clean when inserted into the center of the loaf, about 40 to 45 minutes. Remove from oven and brush with a tablespoon of melted butter if desired. Cool for at least 30 minutes before slicing. Serve slightly warm or at room temperature.