Chocolate cupcakes with salted caramel swiss meringue buttercream

My manager's birthday was coming up at work, and I knew I wanted to make her something special to share with our team. I brainstormed some ideas, but nothing was coming to me. Then I remembered that I had about 3/4 cup of salted caramel left over from my salted caramel apple pie. Yes - I could make salted caramel cupcakes! 

Well, not so much. You see, I had limited time to make this on a weeknight, so I didn't want to make a cupcake base that I wasn't already familiar with (to save time). I loved the cake from these triple chocolate cupcakes and decided to use that recipe and use the leftover salted caramel to make a Swiss meringue buttercream.

Again, because I didn't want to bake 30-some cupcakes, I halved the recipe below (changes are not reflected). Two more changes that I made (again, changes not reflected below) were to replace the 1/2 cup of sour cream (remember, I halved the recipe) with a 6 oz container of plain Greek yogurt, and to cut back on the butter to 1 stick instead of 1 and a half sticks. I knew that the Greek yogurt would provide a lot of the moisture needed for these cupcakes so I opted to cut back on the butter to make up for the extra yogurt that I used.

While the salted caramel swiss meringue buttercream was great, I didn't think that the cupcake base paired as well with this frosting. The dark chocolate cake seemed to be better suited for the triple chocolate cupcakes because the ganache and chocolate frosting intensified the chocolate flavor. The chocolate flavor in these cupcakes were more subdued because the Swiss meringue buttercream didn't bring out the sweetness as much. Regardless, it was still a ridiculously good cupcake (at least my manager said so). Maybe I'm just getting pickier with age.

Cupcakes

• ¾ cup unsweetened Dutch-process cocoa powder
• ¾ cup hot water
• 3 cups all-purpose flour
• 1 tsp. baking soda
• 1 tsp. baking powder
• 1¼ tsp. coarse salt
• 1½ cups (3 sticks) unsalted butter
• 2¼ cups sugar
• 4 large eggs, at room temperature
• 4 tsp. vanilla extract
• 1 cup sour cream, at room temperature (I used a 6 oz container of plain Greek yogurt)

Salted caramel swiss meringue buttercream

• 5 egg whites
• 1-1/2 cup granulated sugar
• 2 cups (4 sticks) unsalted butter, softened
• 1/2 to 3/4 cup salted caramel

Directions

For the cupcakes: Preheat the oven to 350˚ F.  Line your cupcake pans with cupcake liners. In a small bowl, whisk together the cocoa powder and hot water until smooth and set aside.  In a separate medium bowl, mix together the flour, baking soda, baking powder, and salt; set aside.

In a medium saucepan over medium heat, combine the butter and the sugar.  Stir occasionally to combine until the butter is melted.  Turn off the heat, remove the butter mixture from the stove and transfer to the bowl of an electric mixer fitted with the paddle attachment.  Beat the butter and sugar mixture on medium-low speed for about 4-5 minutes until the mixture is cooled.  Add the eggs, one at a time and beat well after each addition.  Add in the vanilla and cocoa mixture and mix until well incorporated.  Turn the mixer to low and alternately add the dry ingredients and sour cream in two batches, starting with the dry ingredients. Beat just until combined.

Distribute the batter evenly among the prepared cupcake liners and fill them about ¾ of the way full.  Bake for 9-10 minutes and rotate the pans. Then bake for another 9-10 minutes or until a toothpick inserted in the center comes out clean.  Cool the cupcakes in the pan for 5-10 minutes, then transfer to a wire rack to cool completely.

For the frosting: Boil about one inch of water in a small saucepan. Once the water boils, immediately turn the heat down to low and allow the water to simmer. 

Place a mixing bowl over the simmering saucepan. Add the egg whites and sugar to the mixing bowl and whisk to combine. Keep whisking and until temperature of the egg white/sugar mixture reaches 140. This will take at least 10 minutes, so be patient.  

In the bowl of a stand mixer fitted with the whisk attachment, beat the heated egg white mixture on medium to medium high speed until you reach stiff peaks. This will take at least 5 minutes. 
 
With the mixer on medium speed, slowly add the butter, one tablespoon at a time. Keep whipping the mixture until all butter has been incorporated. Do not worry if your frosting appears curdled - it will smooth out after a few more minutes of whipping. Finally, add the salted caramel sauce. 

Once the cupcakes have cooled, generously frost the cupcakes with the buttercream. 

Yield: I got 15 cupcakes and enough frosting for at least two dozen (24) cupcakes. With the leftover frosting you can either use it as a filling, or save it for whoopie pies, brownies and other treats.

Source: Cupcakes from this post; buttercream adapted from Shugary Sweets