It’s crazy but true – summer is officially winding down. The weather is cooling off a tad, and my personal Facebook newsfeed is lighting up with first day of school pics. All summer long, I (and pretty much everyone else, I feel sure) try and take as much advantage as possible of all the wonderful summer produce. So the past week or so I’ve been taking stock and asking myself what I haven’t used enough of.
Answer: raspberries. For crying shame, I’ve hardly used them. That is no bueno. So I rectified the situation with a more unusual method for baking with raspberries – let’s make butter cream cake frosting with them. Sure why not?
I can’t take credit for the creativity involved here as this recipe comes from Deb Perelman’s terrific book. I can assure you, though, that this will be one of the more flavorful frostings you’ll ever taste. Oh, and please don’t think you have to stop with raspberries. What I’m really sharing here is a method for berry butter cream frosting. Use whatever berry you prefer or whichever looks best that day. This will work beautifully with blueberries, blackberries, or probably strawberries too.
I did love this cake very much. The frosting tasted so fruity and naturally sweet, but not the least bit cloying. The cake was moist but firm. It was really everything you want in a vanilla cake – quite perfect, really. I think next time I might make cupcakes with this recipe.
A few recipe notes: I didn’t serve the cake right when I frosted it, and out of paranoia, I stuck it in the refrigerator instead of leaving it out on the counter. I don’t know if I absolutely had to do that or not. If anyone has any thoughts on this, please do share them. As such, it was chilled when I had a piece, and I wished I would have tasted it at room temperature, mainly because that’s how I associate cakes. But still quite delicious. The cake itself is very moist, and the frosting is so fruity and flavorful. As usual, Matt took the leftovers to work the next day, where they absolutely evaporated. I think next time, I will make the frosting, refrigerate it in a bowl (which the recipe said you absolutely should do), and then frost the cake right before serving.
12 tbs unsalted butter, at room temperature
2 ¾ cups all-purpose flour
¼ cup cornstarch
1 ¼ tsp baking powder
½ tsp baking soda
¾ tsp salt
1 ½ cups granulated sugar
1 ½ tsp vanilla extract
3 large eggs
1 ½ cups buttermilk, well-shaken
RASPBERRY BUTTERCREAM FROSTING:
1 cup fresh raspberries
16 tbs unsalted butter, at room temperature
4 cups (1 lb.) confectioners’ sugar
First make the cake. Preheat your oven to 350 F. Grease a 9×13” cake pan.
In a medium bowl, whisk together the flour, cornstarch, baking powder, baking soda, and salt. In a large bowl, beat the butter and sugar with an electric mixer at medium speed until the mixture is pale and fluffy. Beat in the vanilla, then the eggs one at a time. Beat well and scrape down the bowl after each addition. On low speed, beat in the buttermilk until just combined (it’s okay if the mixture looks curdled). Add the flour mixture in three batches, blending until each addition is just incorporated into the batter.
Spread the batter evenly in the prepared baking pan. Bake until golden and a cake tester inserted into the center comes out clean, 30 to 40 minutes. Remove from the oven and cool the cake in the pan for 10 minutes. Then run a knife around the edges of the cake and let it cool the rest of the way. Cool completely before frosting, at least 1 hour.
Now make the frosting. Puree the berries in the food processor until they are as smooth as possible. Press the puree through a sieve or other fine-mesh strainer. Discard the solids and seeds. You are looking for about 1/3 to a scant ½ a cup of puree. Set aside.
In a large clean bowl, beat the butter until light and fluffy. Beat in the sugar, 1 cup at a time, beating well after each addition. Add ¼ cup puree and beat until the color is fully incorporated. Add more if desired, but beware: more will intensify the color, which looks beautiful, but it will make the frosting not as stiff. The choice is yours.
Now, either frost the cooled cake right away and serve, or store the frosting in the refrigerator until ready to use.