Strawberry Cupcakes with Strawberry Buttercream Frosting

Ingredients

• 1 2/3 cup cake flour
• 3/4 tsp baking powder
• 1/4 tsp baking soda
• 1/4 tsp salt
• 1/2 cup unsalted butter, softened
• 3/4 cup + 2 Tbsp granulated sugar
• 1 large egg
• 2 large egg whites
• 1/3 cup fresh strawberry puree
• 1/4 cup buttermilk
• 1/2 tsp vanilla extract
• 5 drops red food coloring, optional
• 3/4 cup diced strawberries
• Diced and whole strawberries for topping
• 1/2 cup + 2 Tbsp strawberry puree
• 1/2 cup unsalted butter, nearly at room temperature
• 1/4 cup salted butter, nearly at room temperature
• 2 1/2 – 2 3/4 cups powdered sugar
• 1/4 tsp vanilla extract
• 4 drops red food coloring, optional

Directions

1. Heat the oven to 350 degrees. Sift the cake flour into a mixing bowl, then add the baking powder, baking soda, and salt, and whisk for 20 seconds. Set the bowl aside.
2. In the bowl of an electric stand mixer with the paddle attachment, beat the butter and granulated sugar until the mixture looks light and fluffy. If your paddle does not scrape the bowl as it mixes, pause now and then throughout the process to scrape the sides and bottom.
3. Beat in the egg, then add the egg whites one at a time, mixing after each one. In the liquid measuring cup you used for the buttermilk, whisk the buttermilk with the 1/3 cup strawberry puree and the vanilla extract.
4. Add the dry mixture in three additions, starting and finishing with the flour mixture: mix 1/3 of the flour mixture into the butter mixture, alternate with half of the buttermilk mixture, and mix only until each addition disappears into the batter. Fold in the 3/4 cup diced strawberries.
5. Portion the batter into 12 paper-lined muffin cups, filling each 3/4 full, which is nearly 1/3 cup in each cup. Bake at 350 degrees for 20 – 23 minutes, until a toothpick poked into the center of a cupcake comes out clean. Let the cupcakes sit in the muffin tin for several minutes, then move them to a wire rack and cool completely before frosting.
6. For the Strawberry Buttercream Frosting: Spoon the 1/2 cup + 2 Tbsp strawberry puree into a small saucepan. Warm it over medium-low heat and let it simmer, stirring from time to time, until it has reduced by about 2/3 to 3 Tbsp, about 10 – 14 minutes. Measure it; if it is not quite 3 Tbsp, put it back on the heat and keep simmering, because too much puree will make the frosting runny.
7. Transfer the reduced puree to a small bowl and place it in the freezer until cool. Stir it occasionally so it chills evenly; because the amount is small, it will cool quickly.
8. In the bowl of an electric stand mixer fitted with the paddle attachment, beat the unsalted butter and salted butter until very pale and fluffy, nearly white. If your paddle does not scrape as it goes, stop occasionally and scrape the bowl during mixing.
9. Mix in 1 cup powdered sugar, then add the 3 Tbsp reduced strawberry puree, vanilla extract, and optional red food coloring, and blend to combine. Add the remaining 1 1/2 cups powdered sugar and keep mixing until the frosting is pale and fluffy, adding an extra 1/4 cup powdered sugar if you need a thicker consistency.
10. To assemble cupcakes: Set a small pile of finely diced strawberries in the top center of each cupcake. Pipe the frosting around and over the berries, then finish with a whole small strawberry. Store the cupcakes in an airtight container.