Pre-bake the crust. Preheat oven to 350°F. Using electric mixer, beat butter. Add 1/3 cup of sifted powdered sugar and beat until light and fluffy. Beat in half tsp of lemon zest, ground ginger, crystallized ginger, and pinch of salt. Add 1.5 cups of flour in batches, a 1/4 cup at a time, beating after each addition. Continue to beat the crust batter until it is well combined.

Spread the crust batter evenly over the bottom of a 13x9 inch baking dish. Bake at 350°F for 12-15 minutes or until browned lightly around the edges.

While crust is baking, whisk together the eggs, lemon juice, granulated sugar, remaining 1/2 tsp of lemon zest, 3 TBSP of flour and the baking powder. Whisk until well blended.

Pour the lemon batter over the pre-baked crust. Bake at 350°F for 15 to 20 minutes or until the top is golden. If you want, sift a little additional powder sugar over the top. Let the lemon bars cool in the pan on a rack. Cut and serve.