Step 1

Heat oven to 325°F (if using dark or nonstick pan, heat oven to 300°F). Grease bottom and sides of 13x9-inch pan with shortening or spray with cooking spray.

Step 2

In large bowl, beat 3/4 cup powdered sugar, the granulated sugar and butter with electric mixer on low speed until combined. Beat on medium speed until light and fluffy. Stir in 2 tablespoons lemon peel and 1/4 cup lemon juice. Stir in flour, cornstarch and salt. Press dough in pan with floured fingers.

Step 3

Bake 35 to 45 minutes or until top is light golden brown. Cool completely, about 45 minutes.

Step 4

Meanwhile, in medium bowl, stir all Lemon Icing ingredients until smooth and spreadable. Spread cooled bars with Lemon Icing; let stand 15 minutes or until set. For bars, cut into 6 rows by 6 rows.