You know, I wasn’t even planning to write about these cupcakes. They were just a quickie Valentine’s Day treat I whipped up at the last minute when my original plans went awry. But, they turned out so well, that I just had to share them with you. Isn’t it funny how these things happen? I had originally planned to make a much fussier chocolate cake. Unfortunately, it was a big, fat fail. I didn’t have enough ingredients to remake it, so I then found myself scrambling around my kitchen to find something else that I could do instead. My salvation came to me in a box of Devil’s Food cake mix. Thank you, Duncan Hines!
Ordinarily, I would have never used a boxed cake mix. The crumb is usually too flimsy, and the chocolate ones are never chocolatey enough. But, I was desperate!
To bump up the chocolate factor, I added a few tablespoons of my richest cocoa powder to the mix. I also swapped out a cup of water for the same amount of strong brewed coffee. It worked like a charm! My cupcakes were moist, dense and full of deep, dark chocolate flavor.
I had just enough eggs left to attempt a silky Swiss buttercream to frost the cupcakes with. I also had some of my wonderful slow roasted strawberries  in the fridge, so I decided to use them to flavor the buttercream. The strawberries are roasted in a mixture of sugar and balsamic vinegar, so they are slightly caramelized and intensely flavorful – a perfect addition to the buttercream.
The final flourish to my cupcakes was a super rich bittersweet chocolate glaze drizzled over their tops.
My inspiration for the cupcakes , as well as the glaze recipe, came from one of my new favorite blogs, Sweetapolita.  It is filled to the brim with the most magnificent cakes I’ve ever seen. Honestly, it’s absolutely stunning! If you haven’t ever visited Rosie’s beautiful blog, you must do it now. Go ahead, I’ll wait.
See! Didn’t I tell you it was fabulous?
And, don’t these cupcakes look impossibly indulgent? They are sinfully good! Would you have ever guessed that they got their start in a cardboard box? Neither did all of the people I gave them to. And, don’t you dare tell them, either. I have a reputation to maintain!
Devil’s Food Cupcakes with Roasted Strawberry-Balsamic Swiss Buttercream and Bittersweet Chocolate Glaze
For the cupcakes:
- 1 box Devil’s Food cake mix
- 3 eggs
- 3 tablespoons dark cocoa powder
- 1 cup brewed, black coffee
- 1/3 cup water
- 1/2 cup vegetable oil
For the buttercream:
- 5 large egg whites
- 1 cup plus 2 tablespoons sugar
- Pinch of salt
- 1 pound (4 sticks) unsalted butter, cut into tablespoons, room temperature
- 1 teaspoon vanilla extract
- 1/2 cup roasted, fresh or frozen strawberries, pureed.
For the glaze:
- 4 ounces good quality bittersweet chocolate, coarsely chopped
- 1/3 cup unsalted butter, softened and cut into 1/2″ pieces
- 1 1/2 teaspoons light corn syrup
- Preheat oven to 350 F.
- Prepare the cupcakes according to the instructions on the back of the cake mix box, adding the cocoa powder and coffee for 1 cup of the water. Bake for 18-20 minutes. Remove from the oven and set on a wire rack to cool.
- To make the buttercream: Combine egg whites, sugar, and salt in the heatproof bowl of a standing mixer set over a pan of simmering water. Whisk constantly by hand until mixture is warm to the touch and sugar has dissolved (the mixture should feel completely smooth when rubbed between your fingertips). The temperature on an instant-read thermometer should be 150-160 F.
- Attach the bowl to a stand mixer fitted with the whisk attachment. Starting on low speed, and gradually increasing to medium-high speed, until the mixture is fluffy and glossy, and completely cool (test by touching the bottom of the bowl). This should take about 10 minutes.
- With mixer on medium-low speed, add the butter a few tablespoons at a time, mixing well after each addition. Once all butter has been added, whisk in vanilla and strawberry puree. Switch to the paddle attachment, and continue beating on low speed until all air bubbles are eliminated, about 2 more minutes. Scrape down sides of bowl with a flexible spatula, and continue beating until the frosting is completely smooth. Keep buttercream at room temperature if using the same day.
- To make the glaze: Place the chocolate, butter, and corn syrup in a medium heatproof bowl over a pot of simmering water. Stir the mixture using a rubber spatula until melted and smooth.
- To assemble the cupcakes: Fill a large pastry bag, fitted with a large decorating tip, about 2/3 full. Swirl the buttercream in a circular motion, beginning on the outside rim of the cupcake and moving inward. Gently release pressure when you reach the top of your swirl. Drizzle about a tablespoon of chocolate glaze on top of each cupcake.
The cupcakes are best served the same day, but can be kept in an airtight container for up to 3 days. If refrigerated, bring to room temperature before serving.