Yellow Buttermilk Cupcakes with Swiss Meringue Buttercream

You know you have a winner of a recipe when your sister randomly exclaims on January 16th how awesome the cupcakes you made on Christmas were. She was right, you really can't compare boxed cupcakes to homemade ones. If you have the time, these are so worth it! I made these for the kids for Christmas, but they were definitely a hit with the adults as well. The recipe comes from a cookbook, Martha Stewart Cupcakes, that my sister and niece gave me at my cupcake themed bridal shower:

Yellow Buttermilk Cupcakes

3 cups cake flour (not self rising)

1 1/2 cups all purpose flour

3/4 teaspoon baking powder

2 1/4 teaspoons baking powder

1 1/2 teaspoons coarse salt (I use regular salt for everything)

1 cup plus 2 tablespoons (2 1/4 sticks) unsalted butter, room temperature

2 1/4 cups sugar

5 large whole eggs plus 3 egg yolks, room temperature (I messed up when I was separating the egg whites and yolks of the egss that I had brought to room temp, so I had to use yolks straight from the fridge and it was fine)

2 cups buttermilk, room temperature

2 teaspoons pure vanilla extract

Preheat oven to 350 degrees. Line standard muffin tins with paper liners. Sift together both flours, baking soda, baking powder, and salt. With an electric mixer on medium high speed, cream butter and sugar until pale and fluffy. Reduce speed to medium. Add whole eggs, one at a time, beating until each is incorporated, scraping down sides of bowl as needed. Add yolks, and beat until thoroughly combined. Reduce speed to low. Add flour mixture in three batches, alternating with two additions of buttermilk, and beating until combines after each. Beat in vanilla.

Divide batter evenly among lines cups, filling each 3/4 full. Bake, rotating tins halfway through, until cucakes spring back when lightly touched and a cake tester inserted in centers come out clean, about 20 minutes. Transfer tins to wire racks to cool, 10 minutes; turn out cupcakes onto racks and let cool completely. Cupcakes can be stored overnight at room temperature, or frozen up to two months, in airtight containers.

To finish, use a small offset spatula to spread cupcakes with frosting. Refrigerate up to three days in airtight containers; bring to room temperature and, if desired, decorate with sprinkles before serving.

Swiss Meringue Buttercream
5 large egg whites

1 cup plus 2 tablesppons sugar

pinch of salt

1 pound (4 sticks) unsalted butter, cut into tablespoons, room temperature

1 1/2 teaspoons pure vanilla extract

Combine egg whites, sugar, and salt in the heatproof bowl of a standing mixer. Set over a pan of simmering water. Whish constantly by hand until mixture is warm to the touch and sugar has dissolved (the mixture should feel completely smooth when rubbed in between fingertips).

Attach the bowl to the mixer fitted with the whisk attachment. Starting on low and gradually increasing to medium high speed, whisk until stiff (but not dry) peaks form. Continue mixing until the mixture is fluffy and glossy, and completely cool (testy by touching the bottom of the bowl), 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, switch to the paddle attachment (I forgot this step and continued with the whisk attachment- didn't seem to matter!), and continue beating on low speed until all air bubbles are eliminated, about two 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, or transfer to an airtight container and refrigerate up to three days or freeze up to one month. Before using, bring to room temperature and beat with a paddle attachment on low speed until sxmooth again, about 5 minutes.

Optional- to tint buttercream (or royal icing), reserve some for toning down the color if necessary. Add gel-paste food color, a drop at a time (or use the toothpick or skewer to add food color a dab at a time) to the remaining buttercream. You can use a single shade of food color or experiment by mixing two or more. Blend after each addition with the mixer (use the paddle attachment) or a flexible spatula, until desired shade is acheived. Avoid using too much food color too soon, as the hue with intensify with continued stirring; if necessary, you can tone down the shade by mixing some reserved, untinted buttercream.

Super patient Matt helped me by making these adorable penguins for the tops of the cupcakes. He used Jordan almonds, and dipped them in melted chocolate. He used a ornage sprinkle for their noses and Swedish fish cut up for their feet- how freakin cute?! I bought special sugar at a baking shop in the city for the snow effect on the frosting, and candy canes for the North Pole signs.