Step 1Preheat the oven to 200 °C/ 400 °F (fan assisted), or 220 °C/ 425 °F (conventional).
Step 2Wash and trim the sprouts and remove any bruised leaves. (You'll need 1 kg/ 2.2 lb Brussels Sprouts to get about 800 g/ 1.76 lb trimmed.) Slice fine with a mandoline or pass through the slicing glade of a food processor.