Barbecued Salmon and Vegetables with Chermoulla Sauce

Ingredients

• 2 medium red onions
• 3 medium zucchini, sliced thinly, lengthways
• 340 grams asparagus, trimmed
• 6 180 grams salmon fillets, skin on
• 2 tablespoons olive oil
• 1/2 cup firmly packed fresh flat-leaf parsley leaves
• 1/2 cup firmly packed fresh coriander leaves
• 2 cloves garlic, coarsely chopped
• 1 teaspoon chilli flakes
• 1 teaspoon ground cumin
• 1 teaspoon ground coriander
• 1/2 teaspoon ground turmeric
• 1 tablespoon lemon juice
• 1 tablespoon olive oil
• 1/2 cup (140 grams) greek-style yoghurt