Step 1

Preheat the oven to 220C/425F/Gas Put a large casserole dish and its lid into the oven.

Step 2

In a large bowl, mix the flours, sea salt, sugar and bicarbonate of soda together with your fingers. Pour in the buttermilk, bringing the mixture together as a soft dough. Working quickly (the bicarbonate of soda will start working immediately), shape the dough into a shallow round loaf about 4cm/1½in thick.

Step 3

Remove the hot casserole dish from the oven, dust the inside lightly with flour then lower in the dough. Cover with the lid and return to the oven.

Step 4

The bread should be ready after 25 minutes. Remove from the oven and leave in place for 5 minutes before turning out and leaving to cool slightly before eating. (Soda bread is best eaten warm.)