Lemon Raspberry Layer Cake

Lemon Cake

• 2 1/4 cups (271 g) all purpose flour
• 2 1/2 teaspoons (10 g) baking powder
• 1/2 teaspoon (2 g) fine sea salt
• 1 cup (226 g) unsalted butter, at room temperature
• 1 3/4 cups (347 g) sugar, divided
• Zest of 2 lemons
• 1 teaspoon (5 g)vanilla extract
• 1/4 teaspoon (1 g) lemon extract
• 3/4 cup (6 fl oz) whole milk, at room temperature
• 6 (212 g) egg whites
• 1/4 teaspoon (<1 g) cream of tartar

Filling + Finishing

• 6 (212 g) egg whites
• 1/4 teaspoon (<1g) cream of tartar
• 2 1/4 cups (447 g) granulated sugar
• 1/2 cup (4 fl oz) water
• 2 1/2 cups (567 g) unsalted butter, at room temperature
• 2 teaspoons (10 g) vanilla extract
• 1/2 teaspoon (2 g) lemon extract
• 1 tablespoon lemon zest
• 1 1/2 cups (468 g) raspberry jam

1. Preheat the oven to 350° Fahrenheit. Grease and flour two 8-inch cake pans. In a medium bowl, whisk the flour, baking powder, and salt together to combine.
2. In the bowl of an electric mixer fitted with the paddle attachment, cream the butter, 1 ¼ cups sugar, and the lemon zest until light and fluffy, 4 to 5 minutes. Add the extracts and mix to combine.
3. Add 1/3 of the flour mixture and mix to incorporate. Add half of the milk and mix to combine. Repeat, adding alternate additions of flour and milk until both are fully incorporated.
4. Pour the batter into a large bowl, and wash and dry the bowl of your mixer, and fit it with the whip attachment. Combine the egg whites and the cream of tartar in the mixer bowl and whip on medium speed until frothy, 1 minute.
5. Raise speed to medium and whip to soft peaks. Add the remaining 1/2 cup sugar in a slow, steady stream and continue to whip to medium peaks.
6. Add about a quarter of the egg whites to the bowl with the batter, and mix to combine. You can mix this portion in a bit more vigorously, it will lighten the batter and make it easier to add the rest. Fold in the remaining whites in 2 to 3 additions, folding gently to avoid deflating the batter.
7. Pour the batter evenly into the two prepared pans and bake until a toothpick inserted into the center comes out clean, 30 to 35 minutes. Cool the cakes in the pan for 15 minutes, then unmold onto a cooling rack to cool completely.
8. While the cakes cool, make the buttercream. Place the egg whites and cream of tartar in the bowl of an electric mixer fitted with the whip attachment.
9. Combine the sugar and water in a medium pot and bring to a simmer over medium heat. Stir the mixture until it begins to simmer, then stop stirring and attach a candy thermometer to the side of the pot.
10. If any sugar has washed up on the sides of the pot, brush it away with a pastry brush dipped in cool water. Cook the sugar mixture until it reads 235° Fahrenheit on the thermometer.
11. When the sugar reaches 235° F, begin whipping the egg whites on medium high speed. The idea is to get them to soft peaks by the time the sugar reaches 245° Fahrenheit.
12. When the sugar reaches 245° F, carefully pour it into the mixer in a slow, steady stream while the mixer is running. Continue to whip the mixture until it’s very white, thick, and the bowl is no longer warm to the touch.
13. Begin adding the butter to the mixer. If the meringue is still hot, the butter will just melt and the whole thing will be gloopy—so make sure it’s cooled off. Add the butter 1 to 2 tablespoons at a time, letting each addition incorporate fully before you add the next. Sometimes, the mixture will look broken about halfway through—just keep whipping, it will come around!
14. Add the extracts and lemon zest and mix to combine. Transfer 1/3 of the frosting to a disposable pastry bag and cut a 1/2-inch opening at the tip.
15. To assemble the cake, use a serrated knife to cut the domed tops off of both cakes, then to cut each into two even layers. You’ll have four layers total.
16. Place one cake layer on a turntable (you can use a cake stand or platter if you don’t have one). Pipe a ring of frosting around the edge of the cake - it's like a retaining wall for the jam, so it doesn't ooze out. Place a 1/2-cup scoop of jam in the center of the ring and use an offset spatula to spread into an even layer.
17. Place another cake layer on top and press down gently. Repeat this process until you’ve used all the layers of cake. Chill the cake for 15 to 30 minutes.
18. Apply a crumb coat to the top and sides of the cake using an offset spatula. Chill for 15 to 30 minutes.
19. Frost the top of the cake, then the sides. Remove the excess “wall” of frosting from the upper edge of the cake by swiping across the surface with the spatula. Decorate the cake as desired. Refrigerate if not serving right away, but bring to room temp again before serving.