4 sheets whole-wheat matzo, (5 ounces), broken into pieces
2/3 cup walnut pieces
1 tart green apple, peeled and diced
2 teaspoons freshly grated lemon zest
1 teaspoon ground cinnamon
1 teaspoon minced peeled fresh ginger
1/2 teaspoon salt
2 tablespoons white sweet dessert wine, such as Muscat or ice wine
5 large eggs, at room temperature (see Cake-Baking Tips)
3/4 cup packed light brown sugar
6 egg yolks, (including the 2 reserved in Step 3)
1/4 cup granulated sugar
2/3 cup white sweet dessert wine, such as Muscat or ice wine
9-inch springform pan
1. To prepare cake: Preheat oven to 350 degrees F. Grind matzo in a food processor until powdery; transfer to a medium bowl. Coat a 9-inch springform pan with cooking spray. Place 3 tablespoons of the ground matzo in the pan; turn and tilt to coat the sides and bottom. Transfer the remaining matzo to a bowl and set aside.
2. Put walnuts, apple, lemon zest, cinnamon, ginger and salt in the food processor; process until finely ground. Add 2 tablespoons wine and process until a paste forms.
3. Separate 4 of the eggs; reserve 2 yolks for Step 4 and 2 yolks for the zabaglione sauce (Step 7). Beat the 4 egg whites in a medium bowl with an electric mixer on high speed until soft peaks form.
4. Beat the remaining whole egg and 2 of the egg yolks with brown sugar in a large bowl on medium speed until thick and very creamy, about 4 minutes.
5. Fold the walnut mixture into the egg-yolk mixture using a rubber spatula. Fold in the reserved ground matzo, then fold in the whites until incorporated. Scrape the batter into the prepared pan, spread to the edges and gently rap the pan against the counter a few times so the matzo on the side falls down onto the batter, forming a decorative edge.
6. Bake until lightly browned and a toothpick inserted into the center comes out clean, about 45 minutes. Cool on a wire rack until room temperature, about 2 hours.
7. To prepare zabaglione sauce: Shortly before serving, bring about 1 inch of water to a boil in the bottom of a double boiler (see Tip). In the top of the double boiler, off the heat, beat 6 egg yolks and sugar with an electric mixer on medium speed until thick and pale, about 3 minutes. Beat in 23 cup wine. Adjust the heat and place the top pan over gently simmering water. While maintaining a slow simmer, beat the sauce on medium speed until it is thick enough to hold its shape when mounded up into hills with a spoon, about 5 minutes. Serve the cake with the sauce.
1. Equipment Tip: To improvise a double boiler, set a metal bowl over a pan of simmering water. Allow at least an inch between the water and the bottom of the bowl.
2. Cake-Baking Tips:
3. When using cake pans, they must be greased and floured to create a thin layer of protection against the oven's heat. For greater convenience, use a cooking spray that has flour in the mix, such as Pam for Baking, Baker's Joy or Crisco No-Stick Flour Spray.
4. Whole-wheat pastry flour has less gluten-forming potential than regular whole-wheat flour, making it a better choice for tender baked goods.
5. To properly measure flour when baking, use a spoon to lightly scoop flour from its container into a measuring cup. Once in the measuring cup, use a knife or other straight edge to level the flour with the top of the cup. If the measuring cup is dipped directly into the container--a common mistake--the flour will be packed into the cup and result in extra flour being added to the recipe, yielding tough, dense baked goods.
6. Room-temperature butter for a batter is one of the biggest culinary missteps. In fact, butter must be below 68 degrees F to trap air molecules and build structure. Otherwise, the fat will be liquefied and the cake will be flat. To get "cool" butter: Cut refrigerated butter into chunks and let them sit in a bowl for 5 minutes before beating.
7. Eggs must be at room temperature for the proteins to unwind enough to support the cake's crumb. Either set the eggs out on the counter for 15 minutes or submerge them in their shells in a bowl of lukewarm (not hot) water for 5 minutes.
8. Although you cannot overbeat the eggs, sugar and butter, you can overbeat the flour. If you do, you'll develop the gluten and create a quick bread rather than a layer cake. Beat the flour just until there are no white grains of undissolved flour visible but not until the batter is smooth.
9. MAKE AHEAD TIP: Wrap the cake in plastic wrap and store at room temperature for up to 1 day. Make the zabaglione sauce just before serving.