Heat 2 tablespoons olive oil in a pan over medium-high heat. Season the pork strips with salt and pepper, then sear until golden brown. Remove from the pan and set aside. In a large pot, heat the remaining olive oil over medium heat. Sauté the garlic, shallots, red chilli, ginger and lemongrass for 3-4 minutes until fragrant. Stir in the Thai red curry paste and cook for another minute to develop the flavour.
Pour in the chicken stock and water, then bring to a simmer. Let the broth gently bubble for 15 minutes to allow the aromatics to infuse. Strain the broth to remove the solids and return the stock base to the pot. Add the coconut milk, fish sauce and lime juice to the broth and stir to combine. Taste and adjust seasoning if needed with more fish sauce or lime juice. Simmer gently for 5-10 minutes.
Add the mushrooms and pak choi and cook until just tender, about 3-5 minutes. Meanwhile, in a separate pot, cook the egg noodles according to the packaging instructions and drain well. Return the seared pork to the soup and let it warm through for 2-3 minutes.
To serve:
Divide the egg noodles between the serving bowls. Ladle the hot soup over the noodles and garnish each bowl with fresh coriander, sliced spring onion, chilli and a lime wedge. Serve immediately.
