In small dry skillet, toast sesame seeds over medium-high heat, shaking often, until lightly browned and aromatic, about 1 minute
Transfer to small bowl and set aside. In large pot, combine chicken broth, garlic and ginger; bring to a boil over high heat. Add rice, reduce heat to medium-low and simmer until the rice is tender, 12-15 minutes
Stir in soy sauce and sesame oil; add chile paste to taste. Add chicken and heat until just warmed through. Ladle soup into bowls and garnish with scallions and the reserved sesame seeds.
