Bring a large pot of water to a boil. Once boiling, add the noodles and cook according to the package instructions or until tender.
In the meantime, prepare the sauce: in a small bowl, combine the vegan nước mắm, sugar, water, minced garlic, lime juice, and chili. Taste and adjust spiciness and sweetness to your liking.
Drain the noodles and rinse under cold water. Transfer to a large serving bowl.
Top with bean sprouts, chopped lettuce, chopped cucumber, and pickles. Arrange the sliced egg roll on top of the noodles.
Top with the roasted peanuts, croutons, fried onions, and chopped cilantro. Pour in the nước chấm sauce and stir to combine everything. Serve immediately!
