blackberry cake with raspberry filling

I require a weekend for my birthday. Not a week, certainly not a month, just two days and one evening to do as many as my favorite things as possible and as few of my least favorite things. So wine and a new novel are in; laundry is most definitely out.

Baking and eating my birthday cake is in, but I was really on top of things this year and did all the steps I don’t like so much beforehand. That includes digging around in the messy, nearly unreachable cabinet for pans, lining the pans, and pureeing and straining the fruit. All that was left to do on my actual birthday was add things to the mixer and nibble on frosting while assembling the cake.

I’d originally made this cake for a friend’s bridal shower, but there were two issues: 1) I only got one piece, and 2) I didn’t save any for Dave. He’s pretty adamant about not being a dessert guy and even less so a cake guy, but our friends had such good things to say about the cake after the party that he was sorry he missed it.

So choosing this year’s birthday cake wasn’t a hard decision. Making the cake wasn’t hard either, since I’d left only my favorite parts of baking for my birthday itself. I made a small cake, but I had just enough to last for my entire birthday weekend. Cake everyday is definitely on the list for an awesome birthday.

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Blackberry Cake with Raspberry Filling and Cream Cheese Frosting (cake adapted from Cook’s Illustrated White Cake recipe; filling is just barely adapted from Cook’s Illustrated Raspberry Coulis)

The bride’s wedding colors are Tiffany blue and red, so I originally made a blackberry cake hoping that it would turn out blue, like Elly’s, with raspberry filling as the red. I ended up with a purple cake with pink filling, but no one complained. However, you could mix this up with other berries – blackberries, raspberries, blueberries, or strawberries can be used in both the cake and the filling. Fresh or frozen and thawed berries can be used.

I made a three-layer cake for my birthday, and a four-layer cake for the shower, which I preferred. I love the raspberry filling, so an extra layer of it is very welcome.

For heavy decorations like the roses, increase the frosting recipe by 50% (using 12 tablespoons butter, 12 ounces cream cheese, and 6 cups powdered sugar).

Cake:
¾ cup pureed and strained blackberries (from 8 ounces of blackberries)
⅓ cup milk, at room temperature
1 teaspoon vanilla extract
2¼ (9 ounces) cups cake flour
3 teaspoons baking powder
12 tablespoons unsalted butter, at room temperature
1½ cups (10.5 ounces) sugar
¾ teaspoon salt
4 egg whites, at room temperature

Raspberry Filling:
6 ounces fresh raspberries (or thawed if frozen)
2½ to 3½ tablespoons granulated sugar
pinch table salt
1 teaspoon lemon juice

Cream Cheese Frosting:
8 tablespoons (1 stick) butter, at room temperature
8 ounces cream cheese, at room temperature
pinch salt
2 teaspoons vanilla extract
4 cups powdered sugar

1. For the cake: Heat the oven to 350F. Spray two 8-inch round cake pans with baking spray (or grease and flour the pans). Line with parchment or waxed paper and grease the paper.

2. Using a blender, puree the blackberries. Transfer them to a fine-mesh strainer set over a small bowl; use a spoon or rubber spatula to press the liquid through the strainer, discarding the seeds. Measure ¾ cup of puree. Stir the milk and vanilla extract into the blackberry puree. In a separate small bowl, combine the flour and baking powder.

3. Place the butter, sugar, and salt in the bowl of an electric mixer fitted with the paddle attachment (or a large bowl if using a hand mixer). Beat on medium speed for 2 minutes, until light and fluffy. Add the egg whites one at a time, beating well after each addition. Reduce the mixer speed to low and add one-third of the flour mixture, followed immediately by half of the blackberry mixture, mixing just until incorporated. Repeat with another third of the flour and the rest of the blackberry puree, then the last of the flour. Scrape down the sides of the bowl and mix on medium-low speed for 15 seconds longer.

4. Divide the cake between the prepared pans. Bake for 22 to 28 minutes, or until a cake tester or wooden toothpick inserted into the center comes out clean. Allow the layers to cool in the pans for 5 to 10 minutes. Invert and turn out onto wire racks and peel off the paper liners. Let stand until completely cooled before assembling the cake, at least one hour.

5. For the filling: In a medium saucepan, bring the raspberries, 1 teaspoon water, 2½ tablespoons sugar, and salt to bare simmer over medium heat, stirring occasionally; cook until the sugar is dissolved and the berries are heated through, about 1 minute longer. Transfer the mixture to the blender; puree until smooth, about 20 seconds. Strain through a fine-mesh strainer into a small bowl, pressing and stirring the puree with a rubber spatula to extract as much seedless puree as possible. (there’s no need to wash either the blender or the strainer between the blackberries and the raspberries.) Stir in the lemon juice and additional sugar, if desired. Cover with plastic wrap and refrigerate until cold, at least 1 hour. Stir to recombine before serving. Can be refrigerated in airtight container for up to 4 days.

6. For the frosting: Place the butter, cream cheese, and salt in the (clean) bowl of an electric mixer fitted with the paddle attachment; beat on medium speed until smooth. Switch to the whisk attachment; on low speed, gradually add the powdered sugar, beating until it’s just incorporated. Increase the speed to high and beat for 5 minutes, scraping down the sides of the bowl as necessary.

7. To assemble: To make the cakes easier to handle, wrap each tightly in plastic wrap and chill for at least an hour or up to overnight. Working with one cake at a time, unwrap it and use a serrated bread knife to cut the cakes horizontally in half. If you’re using a cake board, put a small spoonful of frosting in the center of it to glue the cake to the board; if you’re not using a cake board, line the perimeter of your serving dish with strips of wax paper, then put a small spoonful of frosting in the center of the serving dish. Center a layer of cake over the frosting, cut side down. Spread a thin layer of cream cheese frosting over the cake layer. Spoon 3 tablespoons of raspberry filling over the frosting, spreading it to within about an inch of the edge. Center another cake layer over the filling, cut side-down. Repeat the layering of frosting, filling, and cake twice more. Spread a thin layer of frosting evenly over the top and sides of the cake to seal in crumbs. If the layers slide around while you’re spreading the frosting, push wooden skewers from the top to the bottom of the cake in three places to secure the layers. Chill the cake, uncovered, for 30 minutes to 2 hours to set the frosting. Remove the skewers if necessary, then spread the remaining cream cheese frosting evenly over the top and sides of the cake, decorating as desired. Either transfer the cake on the cake board to a serving platter, or carefully remove the strips of wax paper to leave a clean serving platter around the sides of the cake.