Instructions

1. Make the sponge cake
2. Arrange a rack in the middle of the oven and heat the oven to 350ºF. Line the bottoms of 2 (6-inch wide, 2-inch high) round cake pans with parchment paper rounds. Do not grease the pans or parchment.
3. Place 4 large egg whites and 1/4 teaspoon cream of tartar in the bowl of a stand mixer (or medium bowl if using an electric hand mixer). Beat with the whisk attachment on high speed until foamy, about 30 seconds. With the mixer on high speed, gradually pour in 1/3 cup of the granulated sugar and continue to beat until shiny, medium-firm peaks form, about 2 minutes. If using a stand mixer, transfer the mixture to another bowl and wash and dry the mixer bowl and attachment.
4. Place the remaining 1/4 cup granulated sugar, 1/4 cup neutral oil, 1/4 cup whole milk, 3 large egg yolks, 1 teaspoon almond extract, 1 teaspoon vanilla extract, and 1/4 teaspoon kosher salt in the stand mixer bowl (or large bowl if using an electric hand mixer). Beat with the whisk attachment on medium speed until lightened in color, 2 to 3 minutes.
5. Add 1 cup cake flour, 1 teaspoon baking powder, 1/2 teaspoon ground cardamom, and 1/4 teaspoon ground cinnamon. Beat on medium speed until thoroughly combined, about 2 minutes (the mixture will be thick).
6. Add half of the egg white mixture and gently fold in by hand with a flexible spatula. Add the remaining egg white mixture and fold in by hand, being careful to not deflate the egg whites too much.
7. Divide the batter between the cake pans (about 2 1/4 cups or 9 ounces each). Bake until the center of the cake springs back when gently pressed, 23 to 25 minutes (it will not brown much). Place the pans on a wire rack and let the cakes cool completely in the pans, about 1 1/2 hours. Meanwhile, make the milk soak and almond-fennel cream.
8. Make the milk soak
9. Place 3/4 cup whole milk, 1 tablespoon granulated sugar, 2 teaspoons rose water or 1/2 teaspoon rose extract, 20 or 1 big pinch saffron threads, and 1 drop yellow food coloring or 1/4 teaspoon ground turmeric in a small saucepan. Bring to a gentle simmer over low heat, stirring until the sugar is dissolved. Remove the saucepan from the heat and let cool slightly, then refrigerate in an airtight container until ready to use.
10. Make the almond-fennel cream
11. Wash and dry the stand mixer bowl and whisk attachment if needed. Place 2 cups cold heavy cream, 1/4 cup powdered sugar, 4 teaspoons ground fennel, 2 teaspoons vanilla extract, 1 teaspoon almond extract, 1 teaspoon ground cardamom, 1 teaspoon cornstarch, and and 1/2 teaspoon rose water or 1 dash rose extract in the stand mixer bowl (or clean and dry large bowl if using an electric hand mixer). Beat with the whisk attachment on high speed until medium peaks form, about 2 minutes. Refrigerate until ready to use.
12. Assemble the cake
13. Finely chop 1/4 cup cashews and 1/4 cup shelled pistachios, and stir together in a small bowl.
14. Remove the cakes from the pans and discard the parchment. Trim the rounded tops of the cakes with a serrated knife. Cut each cake in half horizontally; you should have 4 cake layers.
15. Place 1 cake layer cut side-up on a cake plate or cake stand. Evenly drizzle 3 tablespoons of the milk soak onto the cake. Top with 1/2 cup of the almond-fennel cream and spread into an even layer with an offset spatula, going all the way to the edges. Evenly sprinkle with 2 generous tablespoons of the nuts.
16. Repeat layering cake, milk soak, almond-fennel cream, and nuts two more times. Drizzle 3 tablespoons of the milk soak onto the cut side of the last layer, then place cut side-down on top of the other layers.
17. Frost the top and sides of the cake with the remaining almond-fennel cream. Refrigerate for 2 to 3 hours to let the cake set. Decorate with more chopped nuts, fresh edible rose petals or flowers, fennel pollen, edible silver or gold leaf, or sprinkles if desired. Keep refrigerated until ready to serve.