Mix all sauce ingredients together. Taste — it should be a balance of sour, sweet, salty and umami.
Heat a wok over very high heat until smoking. Add 2 tbsp oil. Stir-fry the garlic and shallots for 30 seconds.
Add the prawns (or chicken) and cook until just done. Push to the side.
Add the drained noodles and sauce. Toss to coat, cooking for 2 minutes.
Push the noodles to one side. Add 1 tbsp oil to the empty side and scramble the eggs. Once semi-cooked, fold into the noodles.
Add the tofu, bean sprouts and spring onions. Toss everything together for 1 minute. Remove from heat.
Serve garnished with chopped peanuts, lime wedges, dried chilli flakes and fresh coriander.