March 9, 2016, Savannah, Georgia:

I’ve always loved the gamey taste of black walnuts (Juglans nigra), but I can’t say that I always loved dealing with the nuts themselves.  My maternal grandmother had a tree in her immense, magical yard, surrounded by a privet hedge, creating an outdoor room. I always thought the “room” itself was pretty cool, but years later when I became professionally interested in natural history (I was the staff artist at a wildlife preserve for a while), I found out lots more about this native American nut besides the fact that they are very hard to hull; picking the tasty kernels from the shell is almost as hard as getting to the hickory’s (Cayra alba). All ten species of the Juglans genus are noble trees, producing both wood and nuts. I can think other no other tree genus that is as valuable to man and fauna.

All walnuts – and hickories and pecans – are members of the Juglandaceae family of trees – large, aromatic, mostly handsome trees that produce some of the prettiest wood and most delicious foodstuffs on the planet.  Juglans regia L., the so-called “Persian walnut,” is one of the most valuable nut crops in the world. They are wildly popular in Europe, where, in several languages, they share the word for “nut.” Americans tend to call them “English walnuts,” but in England they are simply called “common walnuts.” Their native range has traditionally been said to  have stretched from the  Balkans eastward to the Himalayas, and they are consumed with abandon in Southwest China, where I lived and where they are considered to be a bupin (a restorative health food), often included in medicinal “teas.” But Shui-Ying Hu’s encyclopedic “Food Plants of China” notes that “there is no indigenous species of Juglans regia L. in Europe and Iran,” citing recent floristic studies. “The common walnut is of hybrid origin…. Its first cultivation in Nanjing was between A.D. 222 and 277.” In northern China, the walnut was traditionally fried then mixed with white chicken meat, but it has now been replaced by cashews.

Origins aside, walnuts have been cultivated in Europe for millennia: Romans made both hair dye and a wine (called carynium) from the nuts. They used unripe walnut shells to color cloth. Though they planted the trees throughout northern Europe prior to the rise of Christianity, walnuts were popularized by Middle Age monks who cultivated the trees for their nutritious nuts and medicinal leaves. In the Balkans, where I have also lived,  walnuts fill not only pastries, but sauces, dumplings, and folk customs. In America, walnuts are mostly used in cakes and breads, but in southern and eastern Europe, north Africa, Turkey and the Middle East, they appear in sauces to accompany pasta, meats, and vegetables.  I wrote about tarator, a Bulgarian soup, on August 8, 2011.  The word is from the Ottomans, who ruled in Bulgaria for 500 years, but the soup, with yogurt, is decidedly Bulgarian. Just north of the border, in Transylvania, a favored dish in Jewish homes is pike is stuffed with a filling of walnuts, bread, eggs, and marjoram.

Walnuts are used as a meat substitute in some cuisines. In an Indian restaurant in Washington DC recently I had Akhrot Kofta – walnut “meatballs” that were a sort of dumpling of goat cheese and walnuts swimming in a creamy sauce. They weren’t that good. Which brings me back to BLACK walnuts, which I meant to be writing about!

Black walnuts are about as American as you can get. They were once the majestic kings of the Eastern forest, but they were cut down indiscriminately for their superior wood, which made not only durable fence posts and rails, but also the finest gun stocks. Even old and worn furniture made of black walnut is “bought and sawed thin for the same purpose,” Julia Rogers lamented in her famous Tree Book from 1912. “Do we realize yet the usefulness and the beauty of black walnut wood? The silvery grain, the rich, violet-purple tones in the brown heart wood, the exquisite shading of its curly veinings, and the lasting qualities of the wood? If we did, we would plant groves of it.” While she admitted the limitations of the nuts, because the oil in the kernel goes quickly rancid, thereby limiting its market’s range (in 1912), she failed to point out the single most peculiar trait of Juglans: like all walnuts, the roots, husks, and leaves secrete juglone into the soil. Though used as a dye in clothing, cosmetics, inks, and foods, juglone is a growth inhibitor to some plants and is toxic to others. Rarely will you see weeds growing under a black walnut tree, even in the wild. Hence, my grandmother’s outdoor “room” around her black walnut tree, separating it from her gardens. Juglone is a common ingredient in natural herbicides. It kills apple and birch trees, and tomato plants. The use of black walnut wood in horse bedding can cripple the animals. Strong stuff.

Culinarily, however, the nuts are divine, and taste unlike any other food I can think of. I call them “gamey” for lack of a better word to describe their unique flavor. The flavor is deep, of the woods, with a lingering, slightly metallic aftertaste. They taste more like some smells that come to mind rather than flavors – my grandmother’s house, sorghum syrup being boiled down, or autumn leaves. But perhaps that’s just nostalgia on my part as they evoke childhood memories. At 60% fat, which carries flavor better than any other food element, it’s no wonder they are so powerfully flavored. That fat is why they are favored in baked goods.  They are so famously paired with chocolate that Euell Gibbons, the grandfather of the foraging movement (he died in the 70s) stated, simply, “this is the nut to use in fudge.” My favorite brownie recipe is a dense one made with black walnuts. The recipe appeared on the blog a year ago.

Nearly all black walnuts are hand gathered from the wild; most of the commercial harvest is done in Missouri, where Hammons  has a virtual monopoly on the business. 40% of the nuts harvested go into commercially produced Black Walnut Ice Cream, the third best-selling flavor!  I order one-pound tins of the nuts ($13.99 + shipping) and they last me through 2 or 3 recipes. But I tend to entertain and the following tart that I recently made (I didn’t have a recipe, but I wrote down what I did) served 8. It is delicious and not too sweet like pecan pie. I don’t use corn syrup, but light brown sugar thinned with a little sorghum and bourbon (for flavor).

BLACK WALNUT TART

For the dough:

1-1/2 cups all-purpose flour, plus more for dusting (I use soft southern flour such as White Lily)

1 teaspoon sugar

a good pinch of salt

4 ounces (1 stick) unsalted butter, cold, plus a little room temp butter for greasing the tart pan

1 large egg, beaten

¼ cup, more or less, ice water

For the filling:

5 large eggs

1-1/4 cup light brown sugar

¼ cup liquid such as sorghum syrup, honey, and/or bourbon

2 ounces (1/2 stick) unsalted butter, melted

2 cups chopped black walnuts

For the dough:

Grease a 10” tart pan and set aside. Put the flour, sugar, salt, and butter in a food processor and pulse until the mixture is fairly uniform. Add the egg, turn on the processor, and begin dribbling in the water a little at a time until the dough forms a ball. You may only need a couple of tablespoons of water. Turn the dough out onto a floured counter and form it into a flattened disk. Without overhandling the dough, try to make the disk as perfectly round as you can. Wrap the dough in parchment or wax paper or, if you must, plastic, and put it in the refrigerator for a half hour or in the freezer for 10 minutes.

Preheat the oven to 375º F.

Roll the dough on the floured surface out into a round that is an inch or so wider than the tart pan. Roll it up onto the rolling pin and lay it down in the pan, pressing it lightly into place. Run the rolling pin over the edge to cut off any extra dough, then gently squeeze all along the inside of the rim of the pan, pushing the dough up slightly over the top of the tart pan. If there are any places in the dough that look thin or uneven, you can use the trimmed dough to make repairs.

Line the tart shell with parchment paper and enough pie weights (or beans or rice) to cover the bottom of the dough so that it does not rise up while baking. Bake for 15 minutes, remove the parchment and weights, and poke holes in several places in the dough with the tines of a fork. Return the pan to the oven and bake for another 10 to 15 minutes or until it is lightly brown. Transfer to a rack and allow to cool completely.

For the filling: Separate one of the eggs and put the white aside. Mix the yolk with the other four eggs, the sugar, the liquids (I used two tablespoons of sorghum syrup and 2 tablespoons of bourbon), and the butter until the mixture is smooth. Add the black walnuts and mix well.

Place the tart shell in its pan on a baking sheet. Beat the reserved egg white until slightly foamy, then paint the inside of the tart shell with it. Pour the filling into the shell and bake until the center is set – 30 to 40 minutes. If the edges are browning too rapidly, you can cover them with aluminum foil or with a pie crust edge cover made for the purpose. Allow the tart to cool completely on a rack before serving.

I like to serve this tart with a dollop of crème fraîche, but whipped cream or vanilla ice cream would do as well.