Slice the tomatoes in half lengthways, and top with sliced basil, mint, salt, pepper and sugar. Bake at 160c. for 2 hours, until dried and slightly shrivelled. In a large jug, whisk together all the dressing ingredients until emulsified (thickened). Marinate the chicken in 1/2 cup of dressing, reserving the remainder for later. Allow the chicken to marinate for 1 hour minimum (or up to 4 hours). Heat a non-stick grill pan and cook the chicken fillets over a high heat until cooked through, 2-3 minutes on each side. Transfer the cooked fillets to a plate and keep warm. Steam, microwave or boil the asparagus until tender then refresh under cold water. Halve the avocado, peel off the skin and fan the flesh. Slice the spring onions into diagonal slices and thinly slice the mushrooms. Dice the mango flesh. To make the salad, place the well washed spinach leaves in a large bowl and add the blanched asparagus, sliced spring onions, mushrooms and roasted tomatoes, cut into quarters. Add the reserved dressing and toss thoroughly to coat all the vegetables. Divide the salad evenly amongst individual plates and add some mango cubes and slices of avocado. Top with 2 fillets of chicken, and a generous sprinkling of nut medley. Serve immediately. Per serving: 796 Calories (kcal); 61g Total Fat; (62% calories from fat); 14g Protein; 67g Carbohydrate; 0mg Cholesterol; 2278mg Sodium Food Exchanges: 0 Grain(Starch); 0 Lean Meat; 8 1/2 Vegetable; 1 Fruit; 11 1/2 Fat; 1/2 Other Carbohydrates Converted by MM_Buster v2.0n.