Heat the oil in a medium soup pot over medium-low heat.
Add the shallots and bell pepper slices and cook, stirring frequently, until softened, 3 to 5 minutes.
Add the ginger and curry paste and cook, stirring constantly, for 1 more minute.
Add the chicken broth (if using), coconut milk, fish sauce, brown sugar, lime juice, and turmeric.
Simmer, uncovered, for 10 minutes.
Taste the soup and adjust the seasoning.
Divide the rice and chicken into serving bowls.
Ladle the broth over top.
Generously top with the chopped cilantro and scallions.
Serve with fresh lime wedges.
