Lemon Batter:

1 c. (5 oz./142 g) all purpose flour

3/4 c. (5.5 oz./155g) Sugar

1/4 tsp. salt

1/4 tsp. baking powder

1 Tbsp. Lemon Zest (from 1 large lemon)

1 stick (8 Tbsp.)  butter, melted and cooled

2 large eggs

1 large egg yolk

3 Tbsp. Fresh Lemon Juice

1 tsp. vanilla extract

Lemon Glaze:

3/4 c. (2.75 oz./75g) powdered sugar

1 Tbsp. fresh lemon juice

1/2 tsp. lemon zest

Preheat the oven to 350°F. Grease an 8X8 inch baking pan, and line with parchment- leaving some to hang over the edge of the pan. In a large bowl, whisk together the flour, sugar, salt, baking powder, and lemon zest. In a separate bowl or in a large liquid measuring cup, whisk together the butter, eggs and egg yolk, lemon juice, and vanilla. Stir the wet ingredients into the flour mixture and mix until combined. Spread the batter evenly in the prepared pan. Bake for 18 to 20 minutes, until a toothpick inserted into the center comes out clean or with moist crumbs (the top of the bars should spring back lightly when gently pressed). Don't overbake or they might be dry.

For the glaze, whisk together the powdered sugar, lemon juice, and lemon zest until smooth and combined. After the bars have cooled completely in the pan, drizzle the glaze over the top (since the glaze layer is thin it helps to pour it all across the bars instead of in one puddle before spreading) and use an offset spatula or knife to spread evenly over the bars. Place the bars in the refrigerator for 1 to 2 hours to let the glaze set before lifting them from the pan (using the parchment overhang) and cutting into small squares. These taste best chilled in my opinion, but can be served at room temperature also.