Preheat the oven to 220°C/200°C Fan/425°F, (gas mark 7).
Cut the cauliflower into medium sized florets. Don't make the pieces too small or they will become soggy in the hot oven. Toss the florets in a bowl with the olive oil and a good seasoning of salt and pepper until they are all well coated.
Spread the florets in a single layer on a baking tray and roast in the oven for 10-15 minutes, or until the edges are just turning a little charred.
Now tip the hot cauliflower back into the bowl that you used earlier. Stir in the sultanas, drizzle with the lemon juice and a scattering of curry powder. Taste and adjust each of the flavours until it is perfect for you.
Tip onto a serving dish and sprinkle with the lemon zest and some chopped parsley.