Small whole fish like lemon or Dover sole make perfect individual portions in this special seafood supper for two
First, make the caper paste. Blend the ingredients in a blender or small food processor for 2 mins until you have a smooth-ish purée (if using a food processor, you might need to scrape down the sides once or twice with a spatula). Transfer to a small bowl, cover with cling film and place in the fridge until needed. Can be made 2 days ahead and chilled.
Heat oven to 220C/200C fan/gas 7. Scatter the lemon zest, lemon thyme and shallots onto a baking tray or ovenproof dish. Sprinkle the fish lightly with salt and put it on top of the shallots, skin-side up. Place pieces of butter on each fish and pour in 200ml water – this will steam the fish and keep it juicy.
Put the fish and the prepared tray of potatoes (see recipe in Goes well with) in the oven at the same time and bake both for 10 mins, basting the fish halfway through. While the fish cooks, wilt the greens (see recipe in Goes well with) and take the caper paste out of the fridge to come to room temperature.
Take the fish out of the oven and baste it one last time, then use a cook’s blowtorch to char the skin, if you like. Transfer the fish to a serving plate with some of the shallots and lemon zest. Spoon a little of the caper paste over the fish and serve immediately with the new potatoes and wilted spring greens.