Trim the tops from the fennel. Slice each bulb into 6 and arrange across a large shallow oven tray. Slice the leeks into 1 inch thick rounds and arrange in amongst the fennel.
Step 3
Drizzle over the oil, vinegar and syrup and season with the salt and pepper. Tossing to coat. Cover with foil and bake for 20 minutes. Remove the foil and turn the vegetables and continue to bake uncovered for a further 15 minutes until tender, golden and caramelized.