I almost rammed a fellow shopper's cart in the gourmet-foods aisle of the Up-Island Cronig's, on Martha's Vineyard, one August Sunday evening about ten years ago. We both needed pine nuts for pesto. Only one tiny jar remained, and I spotted it first. As I was putting the jar into my cart, I recognized my rival as a rising academic star from my college days, who today is one of the country's most widely quoted cultural figures. We chatted cordially, discussing mutual acquaintances and the beauty of the basil at the island's farmers' markets, which had inspired each of us to promise our respective hosts a pasta-and-pesto supper. Garlic, cheese, and of course basil were readily at hand, but we both thought those pine nuts were the key to authenticity. To my everlasting shame, I did not transfer the jar from my cart to his on the way to the check-out counter. Nor did I pause to reflect on the irony that two sons of exurban America were nearly coming to civilized blows over a small quantity of nuts—which were imported from China and probably stale anyway—to create an Italian sauce neither of us had tasted growing up. I had no idea that I could have used walnuts instead or simply omitted the nuts, and made two households happy.
I learned about the essential nature of what Marcella Hazan calls "the most seductive of all sauces for pasta," and the ever-fugitive nature of authenticity, during a recent trip to Liguria—the Italian Riviera, dominated by Genoa, which has made pesto its emblem. Pesto's all-in-one convenience helps to explain its popularity: the herbs and seasoning and cheese necessary are concentrated in the fresh, uncooked sauce, whose flavor blooms with the heat of the pasta.
Intensely flavored condiments that could be preserved under oil were prized in a region whose men went to sea for months or years at a time. Basil grew on the hillsides that meet the sea—a landscape more dramatic and forbidding than in the adjacent French Riviera. The landscape, I was told, helps to explain the character of Ligurians, who are hard and hardy, notoriously frugal, and slow to warm but loyal for life. (I traveled with Oldways, a magnet for cooks and writers, which organized the trip with the help of Fred Plotkin, whose definitive Recipes From Paradise contains delightful historical and cultural observations on Liguria.) The pounded-walnut sauces of the regions around the Black Sea, where Genoa maintained trading outposts, are thought to have been an inspiration for pesto; pine nuts were commoner than walnuts along the Mediterranean, so that's what Ligurians used. Garlic has always figured prominently in Ligurian cooking—far more prominently than in that of the southern region of Puglia, for example, even though people assume that garlic reigns only south of Rome. As Franco Solari, one of Liguria's most respected and tradition-minded restaurateurs, told me heatedly when lamenting lily-livered cooks who would denature his region's proudest achievement, "Pesto without garlic is not pesto."
In examining myths around the creation of pesto I was gratified that one—the only true pesto is made with basil grown in Genoa and its hinterlands—shattered upon inspection and close tasting. I was surprised and troubled, however, that the myth I most wanted to demolish remained tauntingly intact: pesto made by pounding and mixing the ingredients by hand with a pestle in a mortar is the best. The name of the sauce, after all, comes from the word for "pestle." I did find a shortcut, though, and ways to improvise a mortar and pestle. I reminded myself of what Patience Gray calls, in Honey From a Weed, a "tremendous antidote to depression": pounding "fragrant things" like garlic and basil.
After reading about the special small-leafed basil of Genoa, I expected to find something completely different from what is available in American gardens and supermarkets. Instead I saw the familiar sweet basil (Ocimum basilicum), but pale, floppy, short, and young. So protective of their signature sauce have Ligurians become that purists use hothouse basil all year round, insisting that only shade and youth will prevent a minty flavor, which they avoid with a vehemence verging on the fanatical. "Plant my basil in the ground five miles away," one greenhouse owner said, "and it will taste of mint." (I considered with sympathy my fellow travelers, who couldn't wait to get home and plant the basil seeds they had bought.) A recent history of Ligurian cuisine suggests that pesto caught on, in fact, only after the building of greenhouses became widespread, in the nineteenth century. This mint phobia is a bit—if I may say it—nutty, and certainly protectionist. American basil can have flavor just as fine, if not quite as fashionably wan, as that of Genoese hothouse basil. If the basil is in your garden, pick it when the biggest leaves are a little less than, say, an inch and a half long. If you're buying it, use the smallest leaves on each stalk, and set aside the larger ones for another use.
The Chinese pine nuts that Americans use—because they are what we find—are denigrated in Italy. (The Italian word for these kernels of hard pine cones is usually spelled without a g—pinoli. The insertion of g by Americans leads to amused puzzlement in Italians, for whom a pignolo is a gratingly fastidious fussbudget.) I familiarized myself on the trip with the bland, somewhat oily flavor of prized Italian nuts, and so did Joe Simone, a marvelously inquisitive and enthusiastic chef who cooks at Tosca, a restaurant in Hingham, on Boston's South Shore. When I went to the Tosca kitchen to try making various pestos, Simone and I compared pine nuts—very expensive Israeli ones, Chinese ones he bought from his supplier, and the nearly identical Chinese ones I found at a local market. The Chinese nuts had the better flavor, and were closer to the pinoli we remembered.
Ligurians sometimes use walnuts in pesto—walnuts fresh off the tree, moist with both water and oil, and very mild; dried walnuts, the kind in stores, give a much sharper taste. In this country almonds and even peanuts in pesto have their fans. If you can't find fresh pine nuts and want to hew close to an Italian line, don't ram another shopper's cart: use walnuts in half or two thirds the amount of pine nuts called for.
There is no substitute for parmigiano-reggiano, the king of cheeses, and luckily you won't need one, because it is widely available here. It is essential for depth of flavor. Ligurians generally use half parmigiano and half pecorino sardo, sheep's-milk cheese whose sweetness rounds out the sauce; Sardinian pecorino, made by artisans or a large but good cheesemaker, such as the family-run Ferruccio Podda, is increasingly sold in American shops. Look at the label closely. Not every pecorino is sweet—especially pecorino romano, which can be extremely salty. Alternatively, a young Spanish manchego will provide the necessary balance, and so will the splendid Vermont sheep's-milk cheese made by Cindy and David Major (802-387-4473)—one of my favorite American cheeses along with Ig Vella's Monterey dry jack, which would also go well in pesto.
The idea is to round out and mellow the sauce, whose bite should come from garlic. Ligurian oil, one of Italy's most delicate kinds, also helps to accomplish this. Early recipes for pesto call for both Ligurian oil and (prepare to be shocked) butter. I didn't try this, but cooks I know in both Italy and America still add butter, to make the texture creamy and the flavor round. In any case, pesto is certainly not the place for strong, peppery Tuscan oil, which will massacre the fragrance of the basil. If you don't want to splurge on Ligurian oil (Rosenthal Wine Merchant, 518-398-1800, sells the beautiful Aldo Armato Ligurian oil for $15 a half liter), or oil from Provence (sweet and comparably expensive), use a reliable and neutral workhorse like Colavita extra virgin.
To taste for yourself how gentle Ligurian pesto is, you can order a bottle—packaged, like all pesto meant to be stored, without cheese—of the Roi brand, from Badalucco, a town with so many olive presses that I encountered several while peering into back alleys. (Zingerman's, in Ann Arbor, at 888-636-8162, imports Roi pesto, and sells most of the cheeses I've mentioned.) At $9.00 for a six-ounce bottle, it's not something you're likely to order very often. But you will see how unassertive Genoese hothouse basil is, and also how little garlic Ligurians use to create a balanced pesto. Chances are you'll decide that you can do better on your own, and chances are you'll be right.
Given that "there are as many recipes as cooks," as Anna Del Conte writes of pesto in her masterly Gastronomy of Italy, here is my attempt at a harmonious sauce that stars garlic and basil.
Yes, you can use a blender, but try not to. After Simone and I arrived at a ratio of ingredients, which required a preliminary round of pestos, we made seven batches of pesto following different techniques. The sweetest and subtlest flavor came from the batch made entirely with mortar and pestle. The consistency was the creamiest, the color the most jewel-like, and the sauce by far the longest-lasting. All the other batches began to separate right away. The worst of all was the batch made start to finish in the food processor, which within minutes was an island of greenish paste floating on an oil slick.