This "hot oiled water blanching" that I talk about is just wilting and cooking lightly any veggie one desires in a pot of boiling water to which has been added a bit of oil, usually veggie oil. One brings a pot of water to the boil, adds some oil (not too much, the oil will coat the veggies, but the oil also provides a "smooth" textural component to the blanched veggies - omitting the oil affects the "mouth feel" of the blanched veggies), then one adds in washed & trimmed veggies and depending on what it is and how cooked you want the veggies to be one waits for the water to return to boiling and/or fishes them out before it does so, or let it come back to a boil and let it boil for however long is needed or desired. It depends on what the veggie is and/or how cooked one wishes it to be and/or how much crunchiness one wishes to retain.
I don't usually use olive oil for this process. It "colors" the flavor and the resulting blanched veggie is oddly "greasy" and cloying when olive oil is used.
The idea is to make the veggie "not raw" and in the process give it this slightly altered taste profile ("semi-cooked") but still retain almost all its previous character. It's one of the most common techniques in Chinese (Cantonese?) cooking. I would consider that even stir-fries of "meat + veggie" in effect does this, albeit the veggie may be "parboiled" or "blanched" in water in the wok over that 35,000 BTU flame without oil, to be fished out and recombined with the rest of the dish later on when there is sauce and oil in the whole.
I do it with almost any leafy veggie I want, both E/SE Asian or Western, within a kind of "taste/texture" profile. Typical would be Gai Lan, Tong Ho (edible chrysanthemum), Spinach of various sorts**, lettuce of almost any kind†† (including the Romaine I described in the previous post) both Oriental and Western, Choy Sum (Yu Choy), etc. However, I would not do this for things like Seng Choy (edible amaranth) or Kai Choy (Chinese "Mustard Greens", Brassica juncea) which don't turn out well with this technique.
With many of the leafy veggies the volume is, of course, greatly reduced after blanching and I'm sure you can imagine which ones those might be.
It also works well with broccoli or cauliflower - as an alternative to steaming them, which would be a well-known Western way with those "harder" veggies. It also works well with stuff like kale - but not really so much collard greens. Western mustard greens work, if you limit the hot water exposure.
In all cases the veggie is blanched to the desired "done-ness", drained (colander) or just fished out; then either eaten as-is (works with flavorful veggies) or dressed with some sauce - such as (Chinese) oyster sauce, or Ponzu sauce, or just soy sauce, even Worcestershire sauce - plus ground pepper or not as one wishes. Some tangy sauce. A classic restaurant dressing for Gai Lan (for example) done this way would be garlic sautéed in oil and quenched w/ oyster sauce (plus other stuff, maybe) then the mixture poured over the blanched vegggies. At home I often simply drizzle oyster sauce straight from the bottle (Lee Kum Kee is my usual brand) over the blanched drained veggie and grate some white or black pepper over it.
Hope this helps.
** Spinach requires a very short blanching time. Often I would simply have the spinach in a large container, pour oil over it, then pour hot (boiled) water over the whole thing and let it simply steep in the oiled hot water (i.e. not on a fire/on the stove over heat) for a short while before draining. With the stout-stemmed "winter spinach" I might do the blanching on the stove over heat barely bring the water up to a boil again.
†† Depending on the lettuce ("robust"/"harder" to delicately soft) the blanching time is adjusted and also whether it is done "on the stove" or "off stove in a container".
Edited by huiray, 28 December 2012 - 10:12 PM.