Place the noodles in a bowl and cover them with warm water. Let them sit for 5 minutes then drain and set aside.
In a small bowl, mix 2 tablespoons lemon juice, 2 tablespoons fish sauce, sugar, and tamarind then set aside.
Place a wok over high heat until sizzling. Add 1 tablespoon oil and swirl to coat.
Add chicken and stir-fry for 3 minutes or until lightly golden.
Add shrimp and stir-fry for 2 minutes or until pink.
Transfer chicken and prawns to a plate.
Add garlic and lemon juice mixture to the wok and cook for 3 minutes or until reduced and syrupy.
Return chicken and prawns to the wok.
Add noodles, chives, and beansprouts. Stir-fry for 2 minutes or until noodles are coated in sauce.
Add peanuts and toss to mix.
Transfer to a bowl and cover to keep warm then wipe the wok clean with a paper towel.
Whisk the remaining fish sauce, pepper, and eggs until well combined.
Heat 1 tablespoon oil in the wok and pour in half of the egg mixture. Swirl to form a thin omelet and cook for 1 to 2 minutes or until almost set. Transfer to a plate.
Repeat with the remaining oil and egg mixture.
Spoon half the chicken mixture onto 1 half of each omelet and fold to enclose.
Serve topped with coriander.