To make the marinade, combine the onion, garlic, ground coriander, smoked paprika, fresh coriander, parsley, lemon juice and olive oil in a food processor and puree into a smooth paste.
Place lamb in a medium mixing bowl and toss with the marinade. Refrigerate covered for at least 2 hours (up to a maximum of 8 hours).
Place a baking tray in the oven and preheat oven to 250°C.
Toss the capsicum with 2 tablespoons of the olive oil and a little salt and pepper. Place onto a preheated baking tray and roast in the oven for 25-30 minutes or until the skin has blistered and browned all over.
Transfer capsicums to a large mixing bowl, cover tightly with plastic wrap and let cool. The steam will help separate the skin from the flesh.
Meanwhile, place the red onions in a large mixing bowl with the remaining 1 tablespoon of oil and the red wine vinegar to marinate. Season lightly with salt and pepper.
Once the capsicums are cool, peel the skin from the capsicum and discard along with the seeds and stem. Cut into thin strips and combine with the red onion slices, season to taste. Preheat a barbecue or char grill pan on high heat.
Thread 3 pieces of lamb and 2 pieces of spring onion onto each skewer, alternating each, so you have 8 skewers total. Season with salt and pepper.
Place the skewers onto the char grill and cook for about 4-6 minutes, turning as needed until the lamb is browned and cooked to medium rare. Remove from the char grill, cover lightly with foil to rest for 2 minutes.
Spoon the pepperonata onto serving plates and place 2 skewers onto each plate. Drizzle with a little extra virgin olive oil and serve with the lemon wedges.
Notes: This recipe is provided care of this sponsor and is not an official MasterChef Australia recipe.