Heat vegetable oil in a saucepan over medium heat. Add onion; cook and stir until slightly softened, 3 to 4 minutes. Stir in grape tomatoes; cook until they begin to release their juices, about 2 minutes. Stir in tomato paste and crushed tomatoes. Cover and cook until fragrant, about 5 minutes.
Remove saucepan from heat. Add water, okra pods, red pepper flakes, chicken bouillon, salt, and curry powder.
Return saucepan to medium heat; simmer soup for 10 minutes. Reduce heat to medium-low and stir in shredded chicken. Simmer until okra is soft and chicken is heated through, stirring occasionally, 8 to 10 minutes.