I already have a strawberry cupcake recipe I really love, but it doesn’t hurt to try new things, right? I have read good things about this recipe on a number of food blogs so it seemed worth a shot. In particular I was interested in the frosting – a strawberry Swiss meringue buttercream. For those who are unfamiliar, Swiss meringue buttercream is an ultra-buttery, silky smooth and rich type of frosting. It takes some time to make, but it is totally worth it (in my opinion). I’ve made it in a few different flavors now including caramel, vanilla, and peppermint and I am smitten. Not only that, I think the strawberry version is the best of all. Ben and I both thought it tasted like a strawberry milkshake or ice cream – in other words, amazing. The cake recipe itself is similar to that of the older version and in that regard I have no preference but for me this frosting is the clear winner.
Some readers have had troubles with the frosting from the original strawberry cupcake recipe being too liquidy, due to adding too much of the fruit puree. That problem is easily remedied by simply adding puree gradually until the frosting has a well balanced flavor and texture. However, if that version doesn’t suit you or you aren’t a fan of cream cheese, now you have this option as well. As I mentioned, this frosting does take some patience in waiting for it to achieve the right texture. Listen, please: it will come together. It can take a very long period of beating but it will thicken up and you will know immediately when it happens. It looks like a magical state change occurs and the frosting is suddenly thick and smooth. If it is at all runny or curdled looking, you need to keep going. I highly recommend you give this frosting a try. I mean really, who doesn’t want frosting that tastes like strawberry ice cream?
For the cupcakes:
2¼ cups all-purpose flour
½ cup cake flour
1 tbsp. baking powder
1 tsp. salt
2 sticks (1 cup) unsalted butter, at room temperature
2¼ cups sugar
1½ tsp. vanilla extract
3 large eggs plus 1 large egg white
1 cup milk
2½ cups finely chopped fresh strawberries*
For the frosting:
1½ cups fresh strawberries (8 oz.), rinsed, hulled and coarsely chopped*
4 large egg whites
1¼ cups sugar
3 sticks (1½ cups) unsalted butter, at room temperature
Additional fresh strawberries*
To make the cupcakes, preheat the oven to 350˚ F. Line cupcake pans with paper liners. In a medium bowl, combine the all-purpose flour, cake flour, baking powder and salt; whisk to blend. In the bowl of an electric mixer, combine the butter, sugar and vanilla. Beat on medium-high speed until light and fluffy, about 3 minutes. Beat in the eggs and egg white one at a time, mixing well after each addition and scraping down the sides of the bowl as needed. With the mixer on low speed, add the flour mixture in two additions alternating with the milk, mixing each addition just until incorporated. Gently fold in the chopped strawberries with a spatula.
Divide the batter between the paper liners, filling each about ¾-full. Bake until light golden and a toothpick inserted in the center comes out clean, about 25-28 minutes, rotating the pans halfway through baking. Allow to cool in the pans a few minutes, then transfer to a wire rack to cool completely.
To make the frosting, place the strawberries in a food processor or blender. Puree until completely smooth. Combine the egg whites and sugar in a heatproof bowl set over a pot of simmering water. Heat, whisking frequently, until the mixture reaches 160° F and the sugar has dissolved. Transfer the mixture to the bowl of a stand mixer** fitted with the whisk attachment. Beat on medium-high speed until stiff peaks form and the mixture has cooled to room temperature, about 8 minutes. (The bowl should be cool to the touch.) Reduce the speed to medium and add the butter, 2 tablespoons at a time, adding more once each addition has been incorporated. If the frosting looks soupy or curdled, continue to beat on medium-high speed until thick and smooth again, about 3-5 minutes more (or longer - don’t worry, it will come together!) Blend in the strawberry puree until smooth and completely incorporated, scraping down the sides of the bowl as needed.
Fill a pastry bag fitted with a decorative tip with the frosting. (I used a large, unlabeled star tip to frost these cupcakes.) Frost cooled cupcakes as desired, and garnish with fresh berries or berry slices.
*Note: I buy organic as much as possible regardless, but strawberries are one of the items where I really notice a huge difference in taste and color. I recommend using organic berries if possible for best results.
**This can theoretically be made using a hand mixer, but will require even more time and a lot of arm strength.