Pour water in a cooking pot. Bring to a boil.
Add tomato and onion. Cover and boil for 5 minutes.
Stir-in Miso paste and cover the pot. Cook for another 3 to 5 minutes
Carefully add the bangus belly. Cook for 5 to 7 minutes in low to medium heat.
Add the Daikon, okra, and green peppers. Cover and Cook for 5 to 8 minutes.
Pour the contents of the sinigang mix package in the cooking pot. Stir. Add fish sauce.
Add the mustard greens. Cover the cooking pot and continue to cook for 4 minutes.
Transfer to a serving bowl. Serve.
Share and enjoy!