Duck breasts are always worth bearing in mind when you have to get something together quickly. Follow a proper recipe, as below, or just slash the skin side diagonally at about 1cm intervals, douse with strained ginger marmalade which you’ve made runnier with soy sauce, or honey mixed with orange juice (the sharper the better, and if you cook this in January or February, you should try and get hold of Seville oranges), or grainy mustard mixed with a drop or two of pineapple juice and a pinch of brown sugar. Roast, skin side up, in a hot oven (gas mark 8/220°C for about 20 minutes). I work on an allowance of 1 per person if I’m slicing them up. The meat is rich, and you somehow taste the duck better, get the sense of its flavour and feathery-velvety texture, when it is sliced. I’d just carve into diagonal, thin, but not wafer-thin, slices and spread them out on a large plate for people to take what they want themselves. I wouldn’t give people their own little portion of fanned-out slices on an individual plate. Of course, you can just serve the duck breasts whole, as they are, in which case it might be safer to cook 2 extra per 4 people in case some want seconds: overcatering is always better than not accommodating people’s greed.