Pre-heat the oven to 200ºC
Dab the cod fillets dry with a piece of kitchen towel, then rub in the lemon zest and season with salt and pepper. Set to one side.
Cut the peppers, onions, courgette and tomatoes into evenly sized 3cm chunks. Place in a bowl and spray well with low calorie cooking spray.
Add the garlic granules, herbs, and some salt and pepper, and toss around until the vegetables are well coated. Drizzle over the balsamic vinegar.
Spray the dish or baking sheet with low calorie cooking spray and then spread the vegetables out in an even layer.
Place in the oven and cook for 15 minutes.
After 15 minutes, remove from the oven and give a good shake. Scatter over the olives, lay the cod fillets on the vegetables and return to the oven for 10-12 minutes, depending on the thickness of your cod.
Divide between 2 warmed plates and serve garnished with the remaining lemon wedges.