Perfectly Moist Irish Wheaten Bread

Preheat the oven to 400 degrees F (200 degrees C). Spray a shallow baking pan with cooking spray.

Sift both flours, 2 teaspoons sugar, salt, and baking soda together into a bowl. Cut in margarine until mixture resembles coarse crumbs. Make a well in the center of the mixture and pour in 2 cups buttermilk and oil; stir with a spatula until dry mixture is completely moistened.

Transfer dough to a lightly floured surface and knead gently for no more than 1 minute. Place dough into the prepared pan; pat down and around to form a round loaf. Cut a cross in the top of the loaf with your finger. Brush the top with 1 tablespoon buttermilk, then sprinkle with 1 teaspoon sugar.

Bake in the preheated oven for 30 minutes. Reduce the heat to 375 degrees F (190 degrees C), then rotate the pan and bake for 30 more minutes. Remove from the oven and let cool on a wire rack before slicing.