There are some tastes you never forget. The flavor of wild American black walnuts is one of them.
I first tried black walnuts this fall, when my forager friend, Richard Bailey, gave me a sack of them. I'd been hearing about them for years: from my grandmother, who grew up with them, and from my mother, describing the black walnut cake she used to make with them. They both got a sort of dreamy, far away look when they talked about the nuts---the kind of look people get when they talk about tastes and memories that belong to another time, another place. When I finally bit into a slice of my grandmother's black walnut cake for the first time a few weeks ago, I understood: black walnuts are all wild, all American, all history.
They don't grow on the Cape, not naturally. Their range extends from Western Massachusetts and Vermont out to southern Ontario, down to central Texas, and then east into Georgia and up the coast. But an Austrian couple in Wellfleet planted a tree half a century ago, and each fall, it produces.
The tree itself looks sort of like a locust---compound pinnate leaves and scratchy bark---but it's actually in the hickory family. The nuts are housed in a fleshy husk that's green straight off the tree, then slowly fades to black. They're famously hard to open: Richard Bailey uses a knife and a bench vice, but others have used hammers, rocks, the tires of their cars. Once you get through the husk, you find a hard shell, same as an English Walnut, so you still have to crack that. Finally, you get to the nutmeats, about a cup for every two pounds un-shelled.
It's a lot of work, but when you taste that flavor, you know it was worth it. The recipe my grandmother handed down to me is called Maryland Black Walnut Cake, and it comes from the Shields Chesapeake Bay Cookbook, circa 1990. She used to have an older recipe, the one my great-grandmother made, but that one's gone and this one is close, she says. It calls for all the usuals: flour, butter, sugar, eggs, a little bit of vanilla and baking powder and milk and salt. But then you add the black walnuts---1 and 1/2 cups of pure ground musk, and it changes the whole game. The flavor is something like really good banana bread soaked in port and black currant cordial with a little bit of smoke mixed in. It's good straight out of the oven but it gets better over the course of a few days---more moist, more pungent, somehow more rare.
I can't hand you a slice through the screen, but I can give you the next best thing: everything you need to bake your own cake, grow your own trees. You can buy black walnuts online, over here, and this company sells the trees online. And thanks to my grandmother, here's that cake recipe.
MARYLAND BLACK WALNUT CAKE
My grandmother talks about a recipe Gransie (her grandmother) used to make, but we can't find that anywhere. Instead, she sent me this recipe card from her files, with a note at the bottom that says "Shields Chesapeake Bay Cookbook, 1990."
2 cups all-purpose flour
1 tablespoon baking powder
1/4 teaspoon salt
1 cup butter
1 and 1/2 cups granulated sugar
1 teaspoon vanilla
3 eggs, separated
3/4 cup milk
1 and 1/2 cup ground black walnuts
Preheat the oven to 350 degrees F. Grease and flour a tube or Bundt cake pan.
Whisk together the flour, baking powder, and salt in a medium bowl.
In a large bowl cream the butter and sugar until they're light and fluffy. Add the vanilla and egg yolks and beat well. Alternately add the dry ingredients and the milk to the creamed butter mixture, mixing well after each addition.
In a separate bowl, beat the egg whites until they're stiff but not dry and gently fold them into the batter along with the ground black walnuts until just combined. Pour the batter into the prepared pan and bake for 30 minutes, or until a piece of straw comes out clean. Turn the cake onto a rack to cool, then dust with confectioners' sugar before serving.