The Fluffiest Cupcakes in the World

• unsalted butter↗1⁄2 cup

  at room temperature

• granulated sugar↗1 cup
• large eggs↗2

  separated, at room temperature

• vanilla extract↗2 tablespoons
• all-purpose flour↗1 1⁄2 cups
• baking powder↗1 1⁄2 teaspoons
• salt↗1⁄4 teaspoon
• milk↗1⁄2 cup
• cream of tartar↗1⁄8 teaspoon

Step-by-step instructions

1. 1

   Preheat the oven to 350°F Line cupcake pans with liners.

2. 2

   With an electric mixer on medium speed beat the butter until soft, about 2 minutes. Add the sugar and beat until light and fluffy, about 3 minutes. Add the egg yolks, one at a time, beating after each addition. Add the vanilla and beat until combined.

3. 3

   In a separate bowl combine the flour, baking powder, and salt.

4. 4

   With the mixer on low speed, alternately add the flour mixture and milk until combined.

5. 5

   In a small bowl with a clean mixer on high speed beat the egg whites until foamy. Add the cream of tartar and continue beating until stiff peaks form. With a rubber spatula stir a little of the whites into the batter to lighten it, then fold in the remaining whites until combined. Do not overmix.

6. 6

   Fill the cupcake liners three-quarters full. Bake for about 15–20 minutes or until a toothpick inserted in the center of a cupcake comes out clean. Cool cupcakes in the pan.