I’m a big fan of the cookbook Heston Blumenthal Home. Whenever I make a Blumenthal recipe, as a rule of thumb, I hardly ever deviate from the directions given (something I do quite excessively with any other recipe) because they simply work. Everything is exactly right: the amounts, ingredients, timings, methods… The result is always guaranteed: mouthwatering recipes! In this book you can find many highlights one of which is this cod with potato and leek sauce. I serve the fish with welted leeks but you can choose other options, like cube potato, cooked spinach, grilled little gems… What makes this dish exceptional is the simplicity of its ingredients and flavours which come together perfectly!

2 cod filets, skinless, of 200 gr each
Groundnut oil
Salt and pepper

50 gr potato (1 small potato)
160 gr leek (about 1 big leak, green top and roots discarded)
1 shallot
1 sprig thyme, 2 sprigs parsley, 1 bay leaf tied together if possible
200 ml fish stock
10 ml double cream
10 ml milk
A knob of butter
Salt and pepper

2 leeks (green top and roots discarded)
1 teaspoon dried tarragon
A knob of butter
Salt and pepper


  1. Peel and thinly slice the potato. Rinse the sliced potato under cold water for 30 seconds.
  2. Peel and thinly slice the shallot and leeks.
  3. Melt the butter in a saucepan over a medium heat and cook the onion and potato for 10 minutes, stirring regularly. Add the leeks and cook for a further 5 minutes.
  4. Pour in the warm fish stock with the herbs and bring to a simmer for 10 minutes or until the potatoes are tender. Remove the herbs and puree the sauce. Add the milk and cream, set aside and keep warm.
  5. For the garnish, slice the 2 leeks in thin rings. Melt the butter in a pan and cook the leeks about 10 minutes until tender. Add the tarragon and season with salt and pepper.
  6. Brush the fish with the oil and season with salt and pepper. Cook them in a pan or grill them under an oven grill or salamander, about 3 minutes on each side.
  7. To serve, spread some of the leek in the middle of a warm plate and place the fish on top. With a handheld blender, froth the sauce and pour it on the fish.