Step 1Preheat oven to 200 °C/ 400 °F (conventional), or 180 °C/ 355 °F (fan assisted). To prepare the vegetables to roast, cut the ends off the asparagus, de-seed the capsicum and slice into 1.5 cm/ 0.6" strips. Cut the zucchini in half lengthwise, and then diagonally slice into 1 cm/ 0.4" slices.