Thread the pieces of leek, the potatoes, the courgette, the mushrooms and the tomatoes on to six skewers.
Put the oil and lemon juice in a bowl.
Halve the passion fruit and scoop the seeds and pulp into the bowl.
Add the honey and seasoning and whisk together.
Brush a little of this dressing over the kebabs.
Barbecue for about 6-8 minutes, turning occasionally until cooked through and golden, brushing once or twice during cooking.
Remove from the skewers and drizzle the remaining dressing over.