(Helminger on the Bauermarkt in Munich, Mariahilfplatz, wednesdays and saturdays)
La version française de ce post est ici.
The French call this cooking "à l'anglaise", and it relies on a heat choc for green vegetables to fix their chlorophylle, ensuring intense taste and splendid colour.
Of course you first have to pick your "haricots verts". They have to be shiny, of a nice intense green without yellow, and firm -- absolutely rule out those whose both ends you can make meet. It should snap loudly when you try to fold them, and there should of course be no string when you do so. Now I like to taste them, raw, on the market. They must be slightly sweet, without bitterness, fruity, develop an interesting aroma. I can't be more specific, because there are many varieties and they taste very different. In any case it should taste fresh and good. As usual (see posts on potatoes and mushrooms), they should be of fairly even size, for you don't want to resize them one by one...
They often say that French haricots verts are the best. This may be true, but only for a a few 72 hours after harvest, and only during the few summer weeks when they are in season. At the seventythird hour, those vegetal Cindirellas turn into some of those disgusting things that you sometimes find in canteens and cans -- yuk. Truth is, the ones from Kenya are usually much better, because they keep well. And they are often thinner.
Of course, if you find some nice fresh ones in June or July, say at Jancar on the organic market (saturday boulevard es Batignolles, Sunday Boulevard Raspail) , or at Thiébault on the market in the 16th (wednesday and saturday avenue du président Wilson), buy them and cancel all lunch appointment immediately.
Now to peeling them. As said, they snap loudly and have no string inside, then they should be washed in cold water without soaking too much. You can keep them like that a few hours, in a strain over a plate if you are too lazy to wipe them, or in a tupperware. Fridge is good.
You need a lot of very boiling, very salty water. Just like for pasta, the proportion is 10g of salt for 100g of vegetables and 1 liter of water. There must be a lot of water so that the temperature does not change much when you throw in the beans, and also to kind of "wash" them of any bitterness. A lot of salt is necessary for the vegetables to have a nice green colour, and the best possible taste. Maybe also because it changes the temperature of boiling water (I don't know). But it matters.
You need a burner strong enough, so you make boil that much water and keep it boiling when the vegetables are thrown in. A large bowl of very cold water is also needed. In winter in the mountains, tap water does the trick, but otherwise you will need ice -- as much as possible. There again, a lot of very cold water to ensure that the beans just taken out of the boiling pot cannot heat the cold water. Must be a choc for them. A heat choc.
Throw the haricots in boiling water one handful after the other (not to interrupt the boiling). Look for an al dente cooking, when the raw taste disappeared (you know, remember you tasted them on the market) and the haricot is still crunchy. Depending on the size and the type of haricot, it will take between 3 and 10 minutes, most often around 7. With experience, you come to judge the cooking degree based on the color. Overcooked haricot is yellow and mushy (as we alas all know). One more reason to brutally stop the cooking.
Which we do: pitylessly grab the beans with a skimmer, out of boiling water, in iced water (scottish shower for Cindirella!). Don't let them soak, for all that chlorophylle that it took us so long to fix (650 words already) would go away in the water. It is ready.
What to do with it? You can reheat them as a side dish, not too much or you would be back to bad yellow beans. Say throw them in the chiken pan just before serving. You can mix different kinds of vegetables, with some sort of juice to bind them (that is the delicious ragoût de légumes of the late Bernard Loiseau).
You can also make a simple salad, with the juice of half a lemon, one big spoon of crème fraîche, salt, pepper, and tarragon. It keeps a solid 12 hours, great for a pique-nique. You can also had tomats.
The technique of "cuisson à l'anglaise" successfully applies to all green vegetables: asparagus, peas, beans, and also leaves of parsley, spinach, nettle, carrots, radishes, watercresson, sorrel. For all those leaves, you can blend them into exceptionally flavorful purees and soups (using the cooking water to liquifiy the puree), which made the happy days of nouvelle cuisine in the late 70's. It is a particular hit with much seafood: nettle and scampi, scallop and parslay, salmon and sorrel are classic examples.
One more: with petits pois, peas: blend them with salted raw cuncumber and you will get a great summer iced soup, which you can keep 24 hours easily (a Guy Savoy recipe).
I learnt it from a commis at Bocuse. But I believe that Robuchon showed it 1255 times in Bon appétit bien sûr.