Salted Caramel Cupcakes

Cupcakes:

1 1/2 cups all-purpose flour
1 teaspoon baking powder
1/4 teaspoon sea salt
1 stick of unsalted butter, at room temperature
1 cup plus 2 tablespoons packed light brown sugar
2 large eggs, at room temperature
1 teaspoon vanilla
1/2 cup plus 2 tablespoons buttermilk

Preheat oven to 325 degrees. Line muffin tins with papers. Combine flour, baking powder and salt; set aside.

Cream butter and brown sugar on medium-high speed until pale fluffy. Add eggs, one at a time, beating until each is incorporated.  Add vanilla.  Mix and scrape down sides of bowl as needed. Add flour mixture in three batches, alternating with two additions of buttermilk, and beating until combined after each.

Divide batter evenly among lined cups, filling each about halfway full.  Bake for about 25 minutes. When done, transfer tins to wire racks to cool 10 minutes; turn out cupcakes onto racks and let cool completely.

Salted Caramel Filling:

1/2 cup sugar
3 tablespoons salted butter cubed
1/4 cup plus 

1 tablespoons heavy cream, at room temperature

Melt the sugar over medium  high heat in a large pot.  Whisk the sugar as it melts and cook until it becomes a deep amber color. Add the butter and stir it in until melted. Pour in the heavy cream (mixture will foam) and whisk until you get a smooth sauce. You may have some lumps but keep stirring until they have melted.  Remove from heat and let cool slightly.  

Cut a small round piece out of the tops of each cooled cupcake and pour in 1 teaspoon of caramel.  Replace the cake piece and set cupcakes aside.

Salted Caramel Buttercream Frosting:

1/4 cup granulated sugar
2 tablespoons water
1/4 cup heavy cream
1 teaspoon vanilla extract
1 stick salted butter
1 stick unsalted butter
1/2 teaspoon sea salt
1 1/2 cups powdered sugar

In a saucepan, stir together granulated sugar and water.  Bring to a boil over medium high heat.  Cook without stirring until mixture turns a deep amber color.  Remove from heat and slowly add in cream and vanilla, stirring until very smooth.  Let caramel cool for about 20 minutes, until it is just barely warm and still pourable.

In a mixer fitted with paddle attachment, beat butter and salt together until lightened and fluffy.  Reduce speed to low and add powdered sugar.  Mix until thoroughly combined.

Scrape down the side of the bowl and add the caramel.  Beat on medium high speed until light and airy, and completely mixed (about 2 minutes).  Mixture should be ready to use without refrigeration.  If your caramel was too hot when added, it will cause your icing to be runny.  If this happens refrigerate for 15-20 minutes.  

Top caramel-filled cupcakes with frosting.