For the Broth, heat oil in 6-quart (5.7 L) stockpot over medium-high heat. Add onion; cook and stir until tender, about 3 minutes. Stir in stock, curry paste, soy sauce, brown sugar, garlic powder and ginger. Bring to boil. Reduce heat to low; cover and simmer 20 minutes. Stir lime juice into broth just before serving.