Cookbooks will tell you that French cutting — the act of cutting green beans lengthwise into thin strips — should be reserved for mature, less tender beans.
A French cut green bean more readily absorbs seasonings, which means you don’t have to over-season to get a balance of flavors. Also, French-cut green beans cook faster, and are easier to bring to the desirable state of tender-yet-crunchy.
I’m pretty sure that French-cut green beans were designed to beat the seven-minute rule.
To preserve the bright green color during cooking, you have a short window to tenderize green vegetables before the boiling water reacts with the heat-sensitive chlorophyll within the vegetable. The longer the exposure, the more dramatic the change in color from lovely green to sickly green. For mature green beans, by slicing them into slender strips, they’ll cook faster and look prettier. Plus, they hold lots more melted butter.
To French cut green beans, a bean slicer is a must. If you only have a pound or two of green beans to deal with, then a hand-held bean slicer will do the trick. There are numerous brands on the market, but my two favorites are the “Zipp Bean Slicer” and the “Krisk Bean Stringer & Slicer.” The latter is a fancy instrument designed with a spring-hinged tunnel that conforms to each beans diameter, and a sharp blade that whisks away the string as the bean is pushed through the slicing mechanism. The Zipp Bean Slicer is dandy too and just a tad more basic. No springs, no hinges, just seven sharp blades built to slice through green beans as clean as a whistle.
For “company batches” of French-cut beans, I pull out my little hand-crank French bean slicer. It’s a slick kitchen tool that attaches to a counter top. To operate it, you feed a handful of fresh green beans into the hopper while turning the crank. Beans are sliced into slender French cut slices in short order. I found mine at a local kitchen ware store years ago. It’s also available via the internet. Made by NorPro, (NorPro Deluxe Bean Frencher with clamp) it costs around $29. Norpro also sells a hand-held bean slicer like the Krisk Bean Stringer & Slicer.
Preparation and cooking: It’s imperative to start with high quality beans. The pod should be unblemished, relatively crisp, with small seeds. Fresh beans will have a slightly fuzzy skin. Avoid limp pods, or pods that are swollen with seeds — an indication that the beans stayed on the vine too long.
Whatever variety of bean you find in your specific area — be it Kentucky Wonder or the ever-popular haricot vert, a very thin, very French variety — the cooking principles are the same. Chlorophyll, the pigment that puts the green in green beans, is heat and acid sensitive. Too much of either and you’ll end up with a bowl of olive drab beans.
Chlorophyll is also sensitive to the acids within the vegetable cells. It’s only after the cell membranes are altered by cooking that these acids are released and able to attack the pigment. If the cooking pot is covered, then the volatile acids condense on the underside of the lid and fall back into the pot. This results in ugly beans.
To preserve color and texture, I prefer cooking green beans in two stages. Stage one is to drop the beans into a large pot of boiling water. As soon as the water returns to a boil simmer for about 1 to 3 minutes — just until the beans are barely tender. Whisk the pot of beans over to the sink, strain through a colander, then plunge the beans into a large bowl of ice water to stop the cooking process.
At this point the beans can be patted dry, covered and refrigerated for several hours or overnight if necessary, and stage two (whatever procedure called for in your recipe, such as braising or sauteing) applied just before serving.