Lemon Cupcakes with Lemon Buttercream Frosting

Ingredients

• 3/4 cup all-purpose flour
• 3/4 cup cake flour
• 1 tsp baking powder
• 1/8 tsp baking soda
• 1/4 tsp salt
• 3/4 cup + 2 Tbsp granulated sugar
• 1 Tbsp lemon zest
• 1/2 cup unsalted butter, softened
• 1 large egg
• 2 large egg whites
• 1/2 tsp vanilla extract
• 1/4 cup + 3 Tbsp buttermilk
• 1 1/2 Tbsp fresh lemon juice
• Simple Syrup
• 1 Tbsp fresh lemon juice
• 1 Tbsp sugar
• 3/4 cup butter, nearly at room temperature, I used 1/2 cup unsalted and 1/4 cup salted
• 1 1/2 tsp fresh lemon zest
• 2 1/2 cups powdered sugar
• 1 Tbsp heavy cream
• 1/4 tsp lemon extract
• Lemon slices or lemon drop candies and mint leaves for decorating, optional

Directions

1. Heat the oven to 350 degrees. Sift the all-purpose flour and cake flour into a mixing bowl, then add the baking powder, baking soda and salt. Whisk for 20 seconds, and put the bowl aside.
2. Combine the 3/4 cup + 2 Tbsp granulated sugar and the lemon zest in a food processor, and pulse until the mixture is finely textured, about 1 minute. Add the butter and lemon sugar to the bowl of an electric stand mixer with the paddle attachment, and beat until the mixture looks light and fluffy. If your paddle does not scrape the bowl as it runs, pause now and then during mixing to scrape the sides and bottom. Beat in the egg, then add the egg whites one at a time, mixing the vanilla in with the second egg white.
3. In the liquid measuring cup you used for the buttermilk, whisk the buttermilk together with the lemon juice. Add 1/3 of the flour mixture to the butter and egg mixture, mixing only until it disappears. Mix in 1/2 of the buttermilk mixture just until incorporated. Do the same flour and buttermilk additions once more, then blend in the final 1/3 of the flour mixture. Scrape the bowl along the sides and bottom.
4. Spoon the batter into 12 muffin cups lined with paper liners. Bake in the 350 degree oven until a toothpick poked into the middle of a cupcake comes out clean, about 18 – 20 minutes. Take the pan from the oven, let the cupcakes rest in the tin for a few minutes, then move them to a wire rack while you make the syrup.
5. For the simple syrup, whisk 1 Tbsp lemon juice with 1 Tbsp granulated sugar in a small bowl until the sugar dissolves. Brush the syrup onto the warm cupcakes, using all of it, about 2 light coats for each one. Let the cupcakes cool all the way.
6. For the lemon buttercream frosting, place the butter and lemon zest in the bowl of an electric stand mixer fitted with the paddle attachment. Beat on medium-high speed until the butter is extremely pale and fluffy, almost white. If the paddle is not the scraping kind, stop occasionally as you mix and scrape the bottom and sides of the bowl. Beat in 1 cup powdered sugar, then mix in the lemon juice, cream, vanilla extract and lemon extract. Add the remaining 1 1/2 cups powdered sugar, and continue beating until the frosting is airy and fluffy, about 4 – 5 minutes more. Spread or pipe the frosting onto the cupcakes. Add lemon slices or lemon drop candies and mint leaves if desired. Store the cupcakes in an airtight container.