Ingredients
The following ingredients have 6 Servings
- 1 1/2 cups (210 g) flour
- 1 1/2 tsp (4 g) cornstarch
- 1/2 tsp (2.5 g) baking powder
- 1/8 tsp baking soda
- 1/4 tsp (1.5 g) salt
- 2 Tbsp (6 g) fresh lemon zest
- 3/4 cup (150 g) sugar
- 1/2 cup (112 g) unsalted butter, softened
- 1 large egg (50 g), at room temperature
- 1 tsp (4 g) vanilla extract
- 6 Tbsp (84 g) unsalted butter, softened
- 1/8 tsp salt
- 1 Tbsp (3 g) fresh lemon zest
- 1 tsp (4 g) vanilla extract (or vanilla bean paste)
- 1 1/2 cups (180 g) powdered sugar
- 1 Tbsp (15 g) fresh lemon juice
Instruction
- Preheat oven to 350°F and line an 8-inch square metal baking pan with parchment paper.
- Whisk together flour, cornstarch, baking powder, baking soda, and salt in a small bowl. Combine lemon zest and sugar in a food processor and pulse for 1 minute to combine. Beat butter and lemon-sugar in a large mixer bowl at medium speed until creamy. Beat in egg and vanilla until combined. Reduce speed to low and gradually add flour mixture; beat just until incorporated.
- Scrape dough into prepared pan and use a piece of wax paper lightly coated with nonstick spray to press dough evenly into pan. Bake bars for 22 to 24 minutes, until edges are golden, top is set, and a toothpick inserted in the center comes out clean. Cool completely in baking pan on a wire rack.
- For the frosting, beat butter and salt in a large mixer bowl on medium speed until smooth. Beat in lemon zest and vanilla. Reduce speed to low and beat in powdered sugar until incorporated. Add lemon juice and mix on low speed until combined, then beat on medium speed for 1 minute, until light and airy.
- Lift parchment and place cookie bars on a cutting board. Use an offset spatula to swirl frosting over the bars and top with lemon zest or sprinkles. Chill for 15 minutes in the refrigerator to set frosting before cutting into bars with a sharp knife. Store leftover bars in an airtight container in the refrigerator for up to 3 days.
