Steamed flathead with spinach and lemon sauce

Instructions

1. Prepare a bamboo steamer set over a large pot of boiling water. Line the bamboo steamer with a sheet of baking paper. Steam the potatoes for 20-30 minutes, or until very tender, then remove from the steamer to a plate and allow to cool. Add the fish to the steamer and steam for a further 6 minutes, then remove and sprinkle with salt. Keep warm.
   
2. To make the spinach and lemon sauce, melt 20 g butter over medium heat in a small saucepan. Add the onion and garlic and cook, stirring, for 3-4 minutes, or until fragrant. Stir through the wine and bring to a light simmer. Cook, until the wine has reduced by half, then stir through the fish sauce, baby spinach leaves and parsley. Add the seafood (or chicken stock) and bring to a simmer for 1 minute, then transfer the contents of the saucepan to a high-speed blender with the lemon juice. Blend to a smooth purée, then with the blender running, gradually add the remaining cubes of chilled butter to emulsify to a smooth sauce. Season with a generous pinch of salt and pepper.
   
3. To serve, thickly slice the potatoes. Divide the flathead fillets and potatoes between serving plates and sprinkle the potatoes with salt and black pepper. Spoon over a generous amount of spinach and lemon sauce over the fish. Drizzle with a little extra virgin olive oil and serve with extra lemon wedges.