Set your oven to 350°F (175°C) and get three 9-inch cake pans ready. If you don't have three pans, no worries, just bake in two batches! 

Line the bottoms with parchment paper and coat the sides with nonstick cooking spray that includes flour, or simply grease and flour the pans. This guarantees your cakes release effortlessly without sticking.

In a medium bowl, whisk together the buttermilk, egg whites, and vanilla and almond extracts. Set this aside for later.

In the bowl of a stand mixer, mix together the cake flour, sugar, baking powder, and salt.

Blend on low speed until the dry ingredients are evenly combined. Cut the butter into small cubes and slowly add them to the dry mixture, mixing on medium-low until the texture looks like moist crumbs.

Now, pour in half of the buttermilk mixture and mix on medium-high speed for about a minute until the batter becomes light and fluffy. 

Scrape down the sides of the bowl, then pour in the rest of the buttermilk mixture, mixing on low speed until it’s just combined.

If the batter looks slightly lumpy, don’t worry! Gently stir it with a spatula to smooth it out.

Divide the batter evenly among your prepared cake pans and bake in the preheated oven for about 22-25 minutes. 

To check if the cakes are done, insert a toothpick in the center, if it comes out with just a few crumbs, they’re ready. 

Let the cakes rest in the pans for 5 minutes, then transfer them to a cooling rack to cool completely.

While the cakes cool, prepare the raspberry filling. Puree the raspberries (either fresh or thawed frozen ones) in a food processor, then strain the mixture through a fine-mesh sieve to remove the seeds. 

Whisk in the cornstarch, sugar, and lemon juice, and bring the mixture to a simmer over medium-high heat, stirring constantly.

Once it begins to simmer, reduce the heat to medium and continue cooking while stirring until the mixture thickens to a spreadable consistency. Let it cool completely in the fridge, this will help it firm up.

Next, make the white chocolate cream cheese frosting. In a microwave-safe bowl, melt the white chocolate and heavy cream together in 30-second intervals, stirring in between until smooth.

Let the mixture cool for 5 minutes. In a large bowl, beat the cream cheese and butter together until smooth and creamy, about 1-2 minutes. 

Add the cooled white chocolate and vanilla extract, then mix until everything is well incorporated. 

Gradually add the powdered sugar, mixing at low speed after each addition, until the frosting is thick and creamy. If it’s too soft, refrigerate it for 30 minutes to help it firm up.

Once the cakes have cooled completely, use a serrated knife to trim the tops, making them flat and even. 

Place the first cake layer on your cake stand or platter. Pipe a ring of frosting along the edge of the cake to create a barrier for the raspberry filling.

Spread half of the raspberry filling inside the ring of frosting, then top it with a generous layer of white chocolate frosting.

Place the second cake layer on top, flipped so the bottom side is up. Repeat the process: pipe the frosting, add the raspberry filling, and top with more white chocolate frosting.

Finish by adding the final cake layer, top side down.

Spread a thin layer of the remaining frosting over the entire cake, smoothing it out evenly. This layer helps trap in any crumbs. Chill the cake for 30 minutes to firm up the crumb coat.

Once the crumb coat is set, spread the remaining frosting over the cake, smoothing it out to your desired finish. 

You can make it as smooth as you like or leave it a little textured. Finally, remove the parchment paper strips from around the base of the cake to reveal a clean edge. Enjoy!