The Right Way to Cook Green Veggies (and Simple Pasta Recipe)
Learn essential kitchen skills–starting with the basics–in our new column, Become a Better Cook. Each post will share a cooking lesson–plus recipes to practice with–courtesy of former Gourmet food editor Ian Knauer.
Practice what you’ve learned so far by making this delicious creamy pasta with asparagus and hard-cooked eggs (find the recipe below).
Photo by Chris Hall.
In the last column, we covered how to boil water. (It sounds simple, but it is a basic technique that everyone needs to master to become a better cook.) This time, we’ll expand on the idea of boiling water to cover blanching, shocking, and we’ll touch on reduction. You can practice these skills by cooking the recipe below. Then you can do what’s most important: eat.
First, a few things you need to know about green vegetables:
1. Vegetables are mostly made up of carbohydrates. Carbohydrate molecules disperse well when boiled, altering avegetable’s texture.
2. Vegetables contain a high percentageof water, so they retain heat and continue to cook after they are removedfrom the heat source (aka: boiling water).
3. Green vegetables are green due to chlorophyll and chlorophyll is destroyed by heat and acids. (More on this later.)
Thesecharacteristics make green vegetables fairly easy to cook with boilingwater, but there are a few tricks that help keep them at the perfecttexture (tender yet slightly crisp) and the perfect color (green, notkhaki).
Food that is”blanched” is immersed in boiling water for a few minutes, then removedand plunged in ice-cold water (“shocked”) to stop the cooking. For example, asparagus will cook in boiling salted water in 5 to 7 minutes. After you reach the righttexture (taste a spear to find out), shock them in ice-cold water. (Photo at left by Chris Hall)
WHY? One reason we blanch green vegetables is to preserve theirvibrant color. The longer chlorophyll boils, the more it disappears(and the less green your veggies are). Actually, it doesn’t disappear;part of it (the magnesium atom) becomes replaced by hydrogen. And thereis a way to help prevent this.
Acidic water has more hydrogenions than alkaline water. What is alkaline? Scientists assign allliquids a number on a pH scale from 0 to 14 that tells us how acidic(more hydrogen ions, ranked 0-6) or how “basic” / “alkaline” (morehydroxide ions, ranked 8-14) it is. Distilled water is a 7, or”neutral.”
The pH of tap water can vary from acidic to basic/alkaline, but if you’re boiling your green veggies inalkaline water, there are less hydrogen ions to destroy the chlorophylland your veggies stay greener.
A simple way to ensure you have alkaline water is to add a very small pinch of baking soda to the pot of boiling water. (More is not better here; add too much and the soda helps to turn your veggies to mush.)
In Bon Appetit‘s Roasted Asparagus and Baby Artichokes with Lemon-Oregano Aioli recipe, the baby artichokes are blanched and shocked in icy water.
Photo by Patricia Heal.
Theother reason we blanch and shock is to control the veggie’s texture–wewant it to be tender and not too crispy but not too flaccid. Thistechnique works well for most green vegetables. The cooking time changes slightly due to thickness and variation in cell structure, but all in all, it’s a great way to cook green beans, okra, fiddlehead ferns, peas, and more.
Both the green beans and the fresh shelled peas in this Polenta with Green Beans, Mushrooms, Peas, and Leeks recipe are blanched and shocked.
Photo by Richard Jung.
Reduction as a topic is far deeperthan just reducing cream, but for the sake of our practice recipe, here’s some quick info. Cream,unadulterated, is already an almost perfect sauce: the fat in it can coatyour mouth in a heavenly way, and it is less likely than milk to form a skin or curdle when boiled down for a sauce. By boiling cream we can remove water and concentratethe fat, creating an even richer sauce. In the recipe below, cream will actas the sauce that ties together pasta, vegetables, and eggs. In order to coat those ingredients most effectively, we’ll need the cream to be around 55 percent fat. Cream is atabout 38 percent fat when you buy it, so we’ll want to reduce the creamby about a third.
So get to it: Practice what you’ve learned, enjoy a greatdinner, and become a better cook.
Pasta with Asparagus and Hard-Cooked Eggs
Active time: 20 minutes
Start to Finish: 40 minutes
**Note this recipe has not been tested in the Bon Appetit Test Kitchen**
1 lb asparagus
6 large eggs
1 lb spaghetti
1 1/2 cups heavy cream
4 tablespoons unsalted butter
1/2 cup finely grated Parmigiano-Reggiano
1/2 cup torn basil leaves
Salt and ground pepper
Trimthe asparagus* and then cut them into 2-inch pieces. Bring a large pot ofwater to a boil and add enough salt to make it taste like the ocean andvery small pinch of baking soda. Cook the asparagus in the boilingwater until it is just tender and still bright green, 5 to 7 minutes.Remove the asparagus from the water and plunge into ice-cold water for 2 minutes then drain. Bring the asparagus cooking water back to a boil.
In anothersaucepan, cover the eggs with room-temperature water. Set the saucepanover medium-high heat and bring just to a boil. Cover the saucepan andremove it from the heat. Let the eggs sit, covered, in the water for 10minutes. Remove the eggs the plunge them in ice-cold water. When coolenough to handle, peel the eggs, then halve them.
Rinse thesaucepan and add the cream and butter. Bring them to a boil and cookuntil the cream is reduced by about one third, about 6 minutes.
Boilthe pasta in the asparagus cooking water until it is al dente. Drainthe pasta (reserve 1 cup of cooking water) and place the pasta back inthe pot. Drain the asparagus and add to the pasta along with the creammixture and the cheese. Season with salt and pepper to taste.
Divide the pasta between serving plates and top with eggs and basil.
*TIP: To trim asparagus, hold onto the top of the stalk with one hand and bend the bottom of the stalk with your other hand. The stalk will snap, separating the woody end from the tender top.
Ian Knauer honed his cooking chops in the test kitchens of Gourmet magazine for over eight years. When not in the kitchen, he’s hunting, tending his beehives, or foraging for dinner wherever it can be found.
Follow him on Twitter @iknauer
Photograph by Romulo Yanes