1. Combine lentils,half the sliced onion and one litre water in a medium saucepan and bring to the boil. Simmer gently for 25 to 30 minutes,until lentils are tender,and drain.
2. Using a sharp knife,score the skin of the duck in a criss-cross pattern. Rub sea salt and pepper into the skin and set aside.
3. In a dry pan,sear the duck skin-side down over gentle heat for 10 minutes,until the fat melts and the skin is crisp. Pour off the fat (cool and refrigerate for future use),turn the breasts and cook for five minutes or until just firm to the touch. Set aside to rest.
4. Pulse the broccoli florets once or twice in a food processor to break them up. Whisk the dressing ingredients together in a bowl. Add the rocket leaves,broccoli,cucumber,radish,walnuts and remaining sliced onion and toss well. Serve with the sliced duck and scatter with poppy seeds.
Tip: Skip cooking your own lentils if it's too hot,and open a can.
For a chilled-out summer dinner,serve Jill'screamy watermelon ice-cream slice for dessert.