1Heat oven to 350°F. Place paper baking cup in each of 24 regular-size muffin cups. In medium bowl, mix flour, baking powder and salt; set aside.
2In large bowl, beat shortening with electric mixer on medium speed 30 seconds. Gradually add sugar, about 1/3 cup at a time, beating well after each addition and scraping bowl occasionally. Beat 2 minutes longer. Add egg whites, one at a time, beating well after each addition. Beat in vanilla. On low speed, alternately add flour mixture, about one-third at a time, and milk, about half at a time, beating just until blended.
3Divide batter evenly among muffin cups, filling each with about 3 tablespoons batter or until about two-thirds full.
4Bake 18 to 20 minutes or until toothpick inserted in center comes out clean. Cool 5 minutes. Remove cupcakes from pans; place on cooling racks. Cool completely, about 30 minutes. Frost with desired frosting.