Heat the annatto oil in a soup pot or pressure cooker.

Once the oil is hot, add the crushed garlic and cook until it turns light brown.

Add the beef shank. Cook one side for about 30 seconds to a minute, then flip it over and cook the other side for a similar amount of time.

Pour in the water and let it come to a boil.

Add the onion, tomato, and beef cube, and give it a good stir.

Toss in the lemongrass, then cover the pressure cooker and cook for 30 minutes. If you're using a regular soup pot, simmer the beef over low heat for 2 to 3 hours, adding more water if needed.

Carefully remove the pressure cooker's cover and apply heat to bring the mixture to a boil again.

Stir in the jackfruit and cook for 5 minutes.

Add the chili peppers and cook for an additional 2 to 3 minutes.

Empty the contents of the sinigang mix packages into the pot, stir, and add the fish sauce. Cook for another 3 to 5 minutes.

Transfer your delicious creation to a serving bowl and enjoy!