The taste of the fennel becomes soft and delicate when cooked this way. It is a perfect foil for oily fish such as mackerel or sardines.
3 fennel bulbs
Sea salt and freshly ground black pepper
1 small bunch of dill, leaves only
Slice the base off the bulbs and remove the tough outer layer. Chop into one-inch pieces and place in a heavy-based saucepan. Add just enough cool water to cover. Add a good pinch of salt and place over a medium heat.
Bring to the boil, then turn down so that the water is just simmering. Cook for 15 minutes, by which time the fennel should be soft when pierced with a fork.
Remove from the heat and drain. Place the cooked fennel into a food processor and blend to a smooth purée.
Add the butter and plenty of black pepper. Chop the dill finely and stir through the purée. Serve.
The purée can be made in advance and gently warmed through before serving.