Pry the lotus seeds apart using the point of a paring knife. if any, remove the pith. Add enough hot water to cover the area by 3 to 4 cm. After three minutes, drain. In a kettle with 3 cups recently boiled water, add the seeds. After bringing to a boil, cover the pot and simmer gently for 15 minutes.

Melt sugar over medium-high heat in a different pot. Turn till slightly colored. Medium-low heat should be used. Swirl the sugar until it gets light brown. Cut the heat off. Swirl until the color is a medium brown. Add 1/2 cup of water. Heat will dissolve sugar if it becomes solid.

Test the sugar for burntness by tasting. If so, throw it away and start over.

Add lotus seeds to the sugar solution. Cook for ten minutes. Verify if the seeds are nearly soft. Give them another five minutes if necessary. Avoid overcooking. Include pandan leaves. Simmer for 5 to 10 minutes or until lotus seeds are completely soft and powdery. Remove the pandan leaves.

If necessary, alter the sweetness and level of the water. Heat up to a medium setting. To thicken soup, gently stir while simultaneously drizzling with the sweet potato flour mixture. When the soup returns to a soft simmer, turn off the heat. Serve warm.