Classic Tangy Lemon Bars

Preheat oven to 350°.

To prepare crust, weigh or lightly spoon 3 ounces (about 2/3 cup) all-purpose flour and whole-wheat flour into dry measuring cups; level with a knife. Combine flours and next 4 ingredients (through 1/8 teaspoon salt) in the bowl of a food processor; pulse to combine. Add butter and oil; pulse 5 to 6 times or until mixture resembles sand. Pour the mixture into an 8-inch square light-colored metal baking pan coated with cooking spray. Lightly press mixture into bottom of pan. Bake at 350° for 20 minutes.

To prepare filling, weigh or lightly spoon 5 ounces (about 1/3 cup) flour into a dry measuring cup; level with a knife. Place 5 ounces flour in a large bowl. Add granulated sugar, 2 teaspoons lemon rind, lemon juice, and 1/8 teaspoon salt; stir well with a whisk. Add eggs; gently stir with a whisk until combined. Pour mixture onto hot crust. Bake at 350° for 23 minutes or just until set. Cool completely on a wire rack. Refrigerate for 2 hours before slicing. Sprinkle with 2 tablespoons powdered sugar.