Prepare your noodles according to package instructions
Mix sauce ingredients in a small bowl, set aside.
In a large wok or skillet over medium-high heat, heat 2tbsp oil. Add shallots and season with salt (again, salt is optional). Cook until golden and crispy, 2-5 minutes. Keep an eye on them so they don't burn, and transfer to a paper towel-lined plate when finished.
Turn heat to high, add sesame oil and remaining 1tbsp vegetable oil. Once the oil is hot, add garlic and Thai chillies. Don't inhale (SPICY), and cook for 10 seconds.
Add onion, cook for 1 minute more
Add chicken and fish sauce/hoisin sauce. Keep the ingredients moving, and fry until cooked, 2-3 minutes.
Add green onion, noodles, and sauce. Cook for about 1 minute, or until sauce is reduced and coats the noodles.
Remove from heat, add basil, and toss. Garnish with crispy shallots and some green onion, and serve!