2 large red onions, each cut into 8 wedges (leave the root on)
1 lemon, juiced
½ tsp wholegrain mustard
large bag rocket, watercress and spinach salad
2 tbsp toasted mixed seeds
8 metal skewers
Mix 3 tbsp oil with the crushed garlic, chilli flakes and rosemary. Thread alternate pieces of mushroom, peach, courgette and red onion onto each skewer – you can get two pieces of everything on each. Brush the kebabs with the flavoured olive oil and season with salt and black pepper, then set aside. The kebabs can be made the day before and kept in the fridge.
Heat the barbecue or a grill to its highest setting. Meanwhile, blitz the avocado, half the lemon juice and 50ml water to a smooth dressing and season to taste. Whisk the remaining lemon juice, remaining ½ tbsp olive oil and mustard together, then toss with the mixed rocket salad and toasted seeds.
Barbecue or grill the skewers for 4-5 mins on each side or until cooked through and nicely charred. Pile onto a platter and serve with the avocado dressing and salad on the side.