How to make pesto, pistou

Summer is basil season and, by now, anyone who grows it likely has an abundance. Basil, a member of the mint family, needs hot weather to thrive.

And why do we grow basil? To make pesto, of course.

We use it in other ways, too, including in Insalata Caprese and basil lemonade, but pesto is basil’s “raison d’etre”, its purpose.

For nearly three decades, pesto has been ubiquitous throughout the year, including in delis that offer pesto pasta salad and in pizza parlors that feature it as an alternative to tomato sauce or, worse with tomato sauce. But basil is a tender creature of summer and so many things it has been put through damage its delicacy.

Let’s consider some of the problems. Basil typically turns black when heated and when it is fully cooked it becomes cloying and unpleasant. And cold pesto, which is what you get in those deli salads, is unpleasant, too, as olive oil is a main ingredient and must be at room temperature or warm to be enjoyable.

Another problem comes with all the different varieties of basil. Some experts suggest that there may be as many as 150 varieties but just one, Genovese basil, is best for pesto. Most varieties are good in green salads. Thai basil is typically one of the the toppings for Vietnamese pho and it is frequently used in curries, too, but it is not the best for pesto.

We shouldn’t talk about pesto without addressing pine nuts, which pose a fairly new problem. Although these tiny nuts were not originally in pesto, they are almost always a part of modern versions. The problem is that most commercially available pine nuts now come from China’s mass plantings of six varieties, two of which are not recommended for human consumption.

Some people, myself included, develop a condition known as “pine mouth,” that typically appears a day or two after eating pine nuts from China. The condition is a persistent bitter and sometimes metallic taste that can last anywhere from a few days to several months. It is quite alarming, as enough time passes before it develops that it is hard to realize the source. When I developed it, there was no information about pine mouth and I grew deeply concerned that something was terribly wrong. Nothing tasted as it should and wine became undrinkable. Lucky for me, I was very busy at the time. I ignored it as best I could and in about three weeks, it vanished.

Because there is no requirement to label the source of pine nuts and because stores that sell them usually don’t know, those of us who have had pine mouth avoid pine nuts unless we can get them from US or Italian sources, neither of which are easy to find.

The other problem is that pine nuts have become very expensive, sometimes as much as $3 an ounce and even more.

You can make pesto without nuts, of course, but another option is to use a different nut. Both walnuts and pistachios work beautifully.

There are two more things to consider when it comes to basil. First, storage: Treat your basil like a bouquet, putting it in a wide-mouthed container with a couple of inches of water in it. Cover the basil loosely with a plastic bag and keep it cool but do not refrigerate it.

Secondly, do not blanch basil before making pesto. Some writers insist this is the best way to keep your pesto green but I think it is the best way to make your pesto bland, as all the brightness and delicacy of basil is destroyed by boiling water. I add some Italian parsley to my pesto; it works perfectly to keep the color bright and the flavors pure.

My final consideration when it comes to basil and pesto may seem ephemeral or even abstract. Like other creatures of summer – apricots, cherries, and melons, for example – pesto tastes best at this time of year. There are plenty of foods to enjoy in other seasons and, honestly, I don’t enjoy pesto in the dead of winter. I want it now, when I can walk outside to pick fresh basil.

And those flowers basil plants begin putting out right about now? Pinch them off and your basil will last longer. They are delicious in green salads.

Makes about 1 ½ cups

This is how I make pesto. It is based on a recipe in Marcella Hazan’s “The Classic Italian Cookbook” (Knopf, 1983). She explains that the original pesto, from Genoa in northern Italy, had no pine nuts and no butter; it was simply a mixture of basil, garlic, cheese, and olive oil. Hazan offers two versions, one for making it in a food processor or blender and one for making it in a marble mortar, along with instructions for how to freeze it. I use a large Japanese mortar known as a suribachi. It is simply a large ceramic bowl that is scored on the inside, which facilitates the grinding process. Suribachis are inexpensive and can be found in Asian markets and most cookware stores.

We don’t always associate butter with Italian cooking but Hazan recommends it and I concur. It adds a voluptuous texture that I find deeply appealing.

2 cups fresh Genovese basil leaves, loosely packed

2 tablespoons roasted pistachios or lightly toasted walnuts

4 garlic cloves, peeled and crushed

1 teaspoon kosher salt, plus more as needed

¼ cup fresh Italian parsley, leaves only

2 ounces (½ cup) Parmigiano-Reggiano, grated

1 ounce (¼ cup) Romano-Pecorino, grated

1/2 cup best-quality extra-virgin olive oil

2 tablespoons butter, optional, at room temperature

Do not wash the basil; brush off any dust or dirt. Remove any stems and gently tear each leaf into 3 or 4 pieces.

Put the basil, pistachios, garlic, salt, and parsley into a suribachi or large marble mortar. Use a heavy wooden pestle to grind the ingredients to a paste. Do not pound the ingredients; instead, move the pestle in a circular motion as you press the ingredients against the side of the suribachi or mortar.

Add the cheeses, mixing thoroughly. If necessary, use a rubber spatula to scrape the pesto from the sides of the mortar. Slowly drizzle in the olive oil, mixing continuously. Taste and correct for salt.

Add the butter and mix well.

Use right away or store in the refrigerator for no more than one day. To store it, put it into a container, pour a thin layer of olive oil on top, and press a piece of parchment or plastic wrap on top, so that the pesto is not exposed to air, which will blacken it and produce off flavors.

Variation: To freeze pesto, do not add cheeses or butter. Spoon the pesto into small jars, top with a thin layer of olive oil, seal tightly, and freeze. To thaw, put the pesto into the refrigerator overnight. Tip the fully thawed pesto into a bowl and beat in the cheeses and butter.

Serving Suggestions:

-Cook pappardelle, fettucccini, or spaghettini in salted water until just done. While it cooks, put the pesto into a large bowl. Save about ¼ cup of the cooking water, drain the pasta but do not rinse it, and put it into the bowl with the pesto, add a spoonful of the cooking liquid and use two forks to lift the pasta over and over to coat it thoroughly, adding more of the cooking liquid as needed to achieve the right texture.

-Add a generous dollop to soup.

-Spoon over baked potatoes.

-Toss with homemade gnocchi.

-For pesto pizza, brush a pizza skin with olive oil, cook, and, when it comes out of the oven or off the grill, use a pastry brush to add a generous layer of pesto.

Makes about 3 cups

Pistou is the French cousin of Italian pesto. Its most traditional use is in Soupe au Pistou, a soup of shell beans, summer vegetables, small pasta, and a big spoonful of pistou; it is similar to minestrone. For other uses, see the suggestions that follow the recipe.

6 garlic cloves, peeled and crushed

Kosher salt

5 cups fresh Genovese basil leaves, torn into pieces

2 tomatoes, peeled, cored, seeded, and minced

Black pepper in a mill

⅔ cup extra virgin olive oil

Put the garlic into a suribachi or large marble mortar, sprinkle generously with salt, and use a wooden pestle to grind the garlic to a paste. Add the basil, a handful at a time, and grind it into the garlic paste. Continue until you have added all the basil.

Use a rubber spatula to fold in the tomato and the olive oil. Taste, correct for salt, and add several turns of black pepper.

Cover and set aside or refrigerate until ready to use.

Serving Suggestions:

-Stir into vegetable soups, bean soups, bread soups, and gazpacho.

-Spread on sandwiches.

-Make bruschetta using sturdy sourdough hearth bread; add cheese (mozzarella fresca or fresh goat cheese), and top with pistou.

-Toss with pasta.

Michele Anna Jordan is the author of 24 books to date, including “Pasta Classics.” Email her at [email protected].