Soak the green beans in clean water for at least 2 hours. If you have more time, soaking them overnight will make them even creamier and reduce cooking time. Once soaked, drain well and set aside.

Wash and peel the sweet potatoes, then cut them into rolling chunks about 2 cm in size. Cutting them evenly helps them cook through without turning mushy.

Place the sago pearls directly into a bowl and set aside. Do not rinse them, as this can cause them to fall apart during cooking.

Add the soaked green beans, sweet potato chunks, and sago pearls into the rice cooker. Add the rock sugar directly — there's no need to dissolve it beforehand.

Pour in the freshly boiled water, making sure all the ingredients are submerged with about 3–4 cm of water above them.

Gently stir to help the sugar begin dissolving and to distribute the ingredients evenly.

Close the lid and select the “Porridge” function. Cook for about 1 hour, adjusting slightly depending on your rice cooker's power, until the green beans are soft, the sweet potatoes are tender, and the sago pearls are mostly translucent.

During cooking, you can open the lid once or twice to gently stir. This helps prevent the sago from sticking to the bottom and the sweet potatoes from sticking to the sides. Stir carefully to avoid breaking the sweet potatoes.

Once cooking is finished, keep the lid closed and let the soup rest for 5 minutes. This allows the sago and green beans to absorb more liquid and improves the overall texture.

Open the lid and gently stir.

Serve warm, or let it cool completely before refrigerating for 30 minutes if you prefer a chilled, refreshing version.