Make the spice paste (rempah): Soak chilies and dried shrimp in 1/2 cup room temperature water for 30 minutes; drain, and squeeze out excess moisture. In blender, combine oil, shallots, and garlic; puree on lowest speed until semi-smooth. Add lemongrass, galangal, candlenuts, turmeric, coriander, white pepper, drained chilies, and shrimp. Puree again until the rempah is semi-smooth.
Make the broth: Heat a 4 quart saucepan over medium-low heat. Add pureed chili paste, and fry over low heat until it is fragrant, and oil begins to separate from puree, 10 to 15 minutes. It should lose any raw aroma, and the raw flavor of the shallots also softens. Add stock; simmer 30 minutes. Add coconut milk and sugar; taste and season with salt as necessary. Bring back to a simmer.
Assemble the soup: Add fish balls and fried bean curd to broth; heat through. Add the par-cooked noodles, and simmer until they are soft and heated through. Divide noodle evenly among 4 to 6 serving bowls. Pour in the broth, and arrange the hot solid ingredients atop the noodles, topping each bowl with bean sprouts, cucumber and laksa leaves or mint. Serve with lime wedges and chili sambal.