Pour the coconut milk and 400ml water into a large ovenproof dish.
Peel and dice the garlic. Add to the dish along with the fish sauce, turmeric and palm sugar. Stir.
Break the noodles into pieces 2-3 inches long and add to the dish. Stir and make sure they are all just covered with liquid - if they aren’t, add a little more water.
Top with the broccoli and cod. Cover with a lid or kitchen foil and put in the oven for 15 minutes.
Remove the oven and add the roughly chopped coriander. Return to the oven for 10 more minutes. Serve immediately.