Step 1Preheat oven to 200°C. Place the baking paper squares on work bench. Top evenly with fish fillets, tomato sauce, olives, capers, thyme and half of the basil leaves. Enclose parcels, securing loosely with string, if needed.
Step 2Transfer fish parcels to a baking tray. Bake for 15 minutes, or until fish is just cooked through.
Step 3Meanwhile, microwave, boil or steam potatoes until tender, adding frozen vegetables mixture for the last 5 minutes of cooking time. Drain. Transfer to serving plates.
Step 4Serve fish parcels with potatoes and vegies. Scatter with remaining basil.