1Sieve the dry ingredients into a large bowl. Scoop up handfuls and allow to drop back into the bowl to aerate the mixture. Add enough buttermilk to make a soft dough. Now work quickly as the buttermilk and sodas are already reacting. Knead the dough lightly--too much handling will toughen it, while too little means it it won't rise properly.
2Form a round loaf about as thick as your fist. Place it on a lightly-floured baking sheet and cut a cross in the top with a floured knife. Put at once to bake near the top of a pre-heated oven, 450 degrees for 30-45 minutes. When baked, the loaf will sound hollow when rapped on the bottom with your knuckles. Wrap immediately in a clean tea-towel to stop the crust hardening too much.
Wheaton bread or Brown soda bread is made in exactly the same but with wholemeal flour replacing all or some of the white flour, this mixture will probably require less buttermilk.