Matzo cake meal stands in for flour in this Passover-friendly dessert. The torte is studded with apples cooked in sweet kosher wine.
Toss apples with lemon juice. Melt butter in a skillet over medium-high heat. Add apples, 1/4 cup granulated sugar, and 1/2 teaspoon cinnamon; toss. Cook until softened, 2 to 3 minutes. Add wine. Cook until almost absorbed and apples are syrupy, about 3 minutes.
Preheat oven to 350 degrees. Coat a 9-inch springform pan with cooking spray. Whisk together yolks and 1/4 cup granulated sugar with a mixer on medium-high speed until pale and thick, about 3 minutes. Transfer to a large bowl; fold in apples, pecans, matzo cake meal, and remaining 1/2 teaspoon cinnamon.
Whisk whites, salt, and remaining 1/4 cup granulated sugar in a clean bowl of a mixer until stiff, glossy peaks form. Working in 3 batches, gently fold whites into batter. Pour into pan. Bake until top is brown and a toothpick comes out clean, about 35 minutes. Let cool.
Run a knife or an offset spatula around edge of torte. Remove from pan. Garnish with confectioners' sugar.
For the best texture, make the torte no more than 8 hours in advance and store it at room temperature.