Pour water in a pot or pressure cooker. Let boil.
Add tomato and onion. Continue to boil for 5 minutes.
Put the beef short rib in the pressure cooker. Cover. Pressure cook for 30 minutes.
Remove the cover of the pressure cooker. Add the watermelon. Continue to boil for 10 to 12 minutes.
Add the Knorr Sinigang na may Gabi Recipe Mix. Stir. Cook for 3 minutes.
Add the snake beans. Cook for 5 minutes.
Add ground black pepper and fish sauce. Stir.
Put the kangkong leaves and stalk into the pot. Cover. Let it stay for 5 to 8 minutes.
Transfer to a serving bowl.
Serve. Share and enjoy!