Method Step 1 To make the stock, crush the cod head on a hard surface. Breaking it into pieces ensures you will maximise the flavour it gives the stock. To make the stock, put the crushed cod head into a pot with the water and bring it to the boil. Let it simmer at a low temperature for 90 minutes, or until it is reduced to about half the amount of liquid. Drain and discard the solids, then keep the stock warm. Step 2 In the meantime, crush or grind the barley (or use ready-made steel-cut oats).

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