KitchenTigress: Lotus Seed Sweet Soup

Lotus Seed Sweet Soup

Lotus seed sweet soup is an old-fashioned Chinese dessert. It's a thick caramel soup with soft, powdery lotus seeds.

I was buying lotus seeds when a fellow aunty shopper who was waiting for her turn asked me how the dried seeds should be cooked.

Whilst I pondered the question (and sized her up), she told me hers were still hard after soaking overnight and simmering for two hours!

Ah yes, my mother had warned me about that. I said to the lady (after deciding she wasn't trying to sell me something), "You mustn't let lotus seeds touch cold water, otherwise they won't soften. You have to wash them in hot water and, when you put them in the pot, the water must be boiling." By soaking lotus seeds in hot water which became cold overnight, she had violated the golden rule: no cold water!

What I told the lady was what my mother had told me. But, whilst I followed Mom's method, I thought her warning about cold water was just an old wives' tale.

I'd never tested my mother's theory, because I couldn't think of any reason why or how water at 30°C or thereabouts could have an effect on lotus seeds. However, judging from what the lady said, it seemed the golden rule might have some basis.

I had no idea whether the fellow shopper went home and tried my mother's method, but I came home and tried hers. I wanted to see if I could replicate her problem, and prove my mother right.

I soaked some lotus seeds in room temperature water for 1.5 hours, then popped them in boiling water. I then placed some dry lotus seeds in a paper pouch, and put that in the boiling water as well.

30 minutes later, the lotus seeds in the paper pouch were perfectly soft and powdery. Those that had been soaked were still hard.

Hah, my mother was right!

The soaked lotus seeds weren't hard throughout but just on the outside. I continued the simmering and after another 30 minutes, the outer layer softened. It was, however, cracked and not powdery, and the inside was too mushy by then.

The unsoaked seeds, in contrast, had a smooth exterior, and were evenly cooked and evenly powdery.

If I'd soaked the lotus seeds longer, like the lady who had left hers overnight, I think the hardened outer layer would have been thicker and harder.

I guess cold water has an effect on the starch in the lotus seeds' outer layer. Why and how exactly, I have no idea. But it's good to know my mother wasn't pulling a fast one on me.

Don't overcook lotus seeds or they'd be mushy and disintegrate. The bitter green piths removed from the seeds may be used to make a "cooling" tea.

lotus seed sweet soup
  • 120 g dried lotus seeds, without peel
  • boiling water
  • 8 pandan leaves, washed and knotted
  • 6 tbsp sugar
  • 1 tbsp water
  • 4 tbsp sweet potato flour, mixed with 2 tbsp water

  1. Using the tip of a paring knife, pry lotus seeds into 2 halves. Remove piths if any. Add enough boiling water to cover by 3-4 cm. Soak 3 minutes and drain. Place seeds in a pot with 3 cups freshly boiled water. Bring to a boil and simmer gently, covered, for 15 minutes.

  2. In a separate pot, melt sugar with 1 tbsp water over medium-high heat. Swirl till lightly coloured. Reduce heat to medium-low. Continue swirling till sugar turns light brown. Turn off heat. Keep swirling till colour is medium brown. With your hand to the side of the pot (to avoid the burst of steam), add ½ cup water. If sugar solidifies, heat to dissolve. Taste to check if sugar is burnt. If it is, discard and make another batch.

  3. Add sugar solution to lotus seeds. Simmer 10 minutes. Check that seeds are almost soft. If not, give them another 5 minutes. Do not overcook. Add pandan leaves. Simmer till lotus seeds are fully soft and powdery, 5-10 minutes. Discard pandan leaves. Adjust water level and sweetness if necessary. Increase heat to medium. Stir gently and, at the same time, drizzle with sweet potato flour mixture to thicken soup. Turn off heat when soup returns to a gentle simmer. Serve hot.