This is a Bon Appetit recipe, and I have changed it only slightly by the addition of vanilla and — wait for it — salt. But seriously: a cake with no salt? What the? I love making the batter because you don't have to cream any butter or anything; you just pour in the oil. Plus, you can get your kids to do most of the work of zesting and juicing the oranges and dealing with the pan. Easy peasy.
Yields 8-10 servings
Heat the oven to 350. Spray a 9-inch-diameter springform pan with nonstick olive oil spray. Place a parchment paper round in the bottom of the pan and spray the paper.
Grind the walnuts in a food processor (or blender) until finely ground but not powdery.
Whisk together the ground walnuts, flour, baking powder, and salt in a medium bowl; set aside.
Using an electric mixer, beat the eggs in a large bowl until frothy, about 2 minutes. Gradually add the sugar, and beat until light, thick, and pale yellow, about 4 minutes. Gradually add the walnut-flour mixture, then add the orange juice, orange peel, olive oil, and vanilla, and beat just until blended. Transfer the batter to the prepared pan.
Place the pan on a rimmed baking sheet (a weensy bit of oil might leak out), and bake cake until tester inserted into center comes out clean, 50 minutes-1 hour; it will puff up and then sink, which seems to be okay.
Cool the cake completely in its pan on a rack. Unless you want to pull it all apart into raggedy pieces, in which case you should try to remove the pan while it's still hot. Sift powdered sugar over the cooled cake and serve.