KF Seetoh, author of "Mankansutra" (the Zagat of Singapore street food), joins Martha to make laksa.
Bring a large pot of water to a boil. Add noodles and cook until slightly softer than al dente, about 5 minutes. Drain and set aside.
In a large pot, heat oil over medium heat and add rempah. Cook, stirring, until oil begins to separate, 6 to 8 minutes. Add 9 1/2 cups water and lemongrass; bring to a boil. Immediately reduce heat to a simmer. Let simmer for 10 minutes.
Add coconut milk, salt, sugar, chicken seasoning, if using, and 5 tofu puffs. Simmer over medium-low heat for 7 minutes. Add noodles and cook for 30 seconds to absorb flavor. Transfer noodles to serving bowls.
Top noodles with gravy, remaining tofu puffs, beansprouts, fishcake, prawns, and scallops. Garnish with laksa and serve immediately.