Dulce De Leche Cupcakes

Ingredients:

• 1 and 3/4 cups  cake flour
• 3/4 teaspoon baking powder
• 1/4 teaspoon baking soda
• 1/4 teaspoon salt
• 1/2 cup  unsalted butter, softened to room temperature
• 1 cup granulated sugar
• 3 large egg whites, at room temperature
• 2 teaspoons pure vanilla extract²
• seeds scraped from 1/2 of a vanilla bean
• 1/2 cup  full-fat sour cream at room temperature
• 1/2 cup whole milk at room temperature

Directions:

1. Preheat the oven to 350°F. Line a 12-cup muffin pan with cupcake liners. Line a second pan with 2 liners - this recipe makes about 14 cupcakes. Set aside.
2. Whisk the cake flour, baking powder, baking soda, and salt together. Set aside.
3. Using a handheld or stand mixer fitted with a paddle attachment, beat the butter on high speed until smooth and creamy - about 1 minute. Add the sugar and beat on high speed for 2 minutes until creamed together. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Add the egg whites, vanilla extract, and vanilla bean. Beat on medium-high speed until combined, then beat in the sour cream. Scrape down the sides and up the bottom of the bowl as needed. With the mixer on low speed, add the dry ingredients until just incorporated. With the mixer still running on low, slowly pour in the milk until combined. Do not overmix. You may need to whisk it all by hand to make sure there are no lumps at the bottom of the bowl. The batter will be slightly thick.
4. Pour/spoon the batter into the liners - fill only 2/3 full to avoid spilling over the sides. Bake for 19-22 minutes, or until a toothpick inserted in the center comes out clean. 
5. Pipe in some dulce de leche after the cupcake is cooled and frost with vanilla buttercream frosting and drizzle with more dulce de leche.
   

    Vanilla Buttercream

   Yield: 2.5 cups

   Ingredients:

   • 1 cup unsalted butter, softened to room temperature
   • 4 - 5 cups  confectioners' sugar
   • 1/4 cup  heavy cream
   • 2 teaspoons pure vanilla extract
   • salt, to taste

   Directions:

   1. With a handheld or stand mixer fitted with a paddle attachment, beat the butter on medium speed until creamy - about 2 minutes. Add 4 and 1/2 cups confectioners' sugar, the heavy cream, and vanilla extract with the mixer running on low. Increase to high speed and beat for 3 full minutes. Add up to 1/2 cup more confectioners' sugar if frosting is too thin or another Tablespoon of cream if frosting is too thick. Add a pinch of salt if frosting is too sweet. (I like 1/8 tsp salt.)
   2. Cover tightly and store for up to 1 week in the refrigerator.