Heat the coconut oil in a large deep pan set over a medium heat. Add the curry paste and garlic and fry for a few minutes, stirring often, until the garlic is fragrant. Add the turmeric and cook for a further minute, stirring.
Fry for a few minutes before adding the turmeric and frying for another minute.
Pour in the coconut milk, followed by the stock. Stir in the sugar and fish sauce. Bring to the boil, then reduce the heat and simmer gently for 5 minutes. Taste and adjust the seasoning, adding more fish sauce or sugar, as needed.
Meanwhile, bring a large saucepan of water to the boil and cook the noodles and wontons according to packet instructions. Add the pak choi for the final 30 seconds. Drain well.
Divide the noodles and wontons between 2 bowls. Ladle over the broth and top with the pak choi. Garnish with spring onions, crispy onions and fresh coriander. Drizzle with chilli oil or peanut rayu and serve sprinkled with peanuts and wedges of lime to squeeze over. Enjoy!