This is a favourite soup of mine. It's clear and very soothing. And when you're simmering this soup, your neighbours would probably know you're having Old Cucumber (Lou Wong Kua in Cantonese) Soup.
Old cucumber is actually matured cucumber. It has a brownish hard skin on the outside. It looks like a melon because it is fat and squat. My vegetable-seller tells me that the older the cucumber, the better it tastes!
Many people shy away from using pork ribs for this soup; they prefer to use chicken thighs without skin. But I like my soups to be robust and flavourful so I tend to use pork ribs. Chicken-based soups taste completely different from pork-based soups. I am fundamentally Chinese in this aspect.
Old cucumber is not only cooling for blistering hot days but is also good for the skin. I read somewhere that it helps to prevent aging! Now that's enough reason for us all to run to the nearest wet market to get some old cucumbers!
Anyway, some people prefer to cut the cucumber into large chunks and de-seed these chunks. (Keep the cucumber skin on, wash and scrub the skin before you slice it up because that keeps the cucumber from 'melting' completely into your soup!). I don't de-seed the cucumber because I actually like chomping on the kuaci-like seeds.
Next, rinse 5-6 pitted dried red dates. Blanch your meat - if you are using pork ribs, blanching is necessary because you want a clear soup. If you are using chicken thighs, remove the skin. Next, for added flavour, I like to soak a few scallops or if none, use some dried oysters.
Bring a pot of water to boil. Add in your meat, chunks of old cucumber, red dates, scallops or dried oysters. Boil furiously for 10 minutes or so. Then lower the fire to a mere simmer, cover the pot and let it simmer nicely for 2 hours. Season with salt before serving.
If I use pork ribs, I usually get rid of the excess oil (which floats to the top) using a fine steel sieve.