lemon bars

(these were originally passed on to me from the mother of my good friend--i played around with the recipe a bit)
Crust
2 cups flour
1/2 cup powdered sugar
pinch of salt
1/4 tsp ground cardamom (optional)
1 cup unsalted butter--melted
Filling
6 large eggs
2 3/4 cups sugar
1 tsp baking powder
6 Tbs flour
2 tsp grated lemon peel
1/2 cup fresh lemon juice
pinch salt

For Crust:  prepare an 8x8 pan by lining with aluminum foil allowing the foil to come up the sides and extend at least an inch.  lightly spray with pan spray.  mix all crust ingredients together and press into pan.  Bake at 350 until just starting to brown.  
For Filling:  In a mixing bowl, with the whisk attachment, beat all ingredients until pale and fluffy.  Pour over hot crust and bake about 20-25 minutes. Cool in pan and refrigerate at least 4 hours before cutting.  Sift powdered sugar over the top and serve chilled.
Variation:  Make 1 1/2 times the crust recipe and use 2/3 for the bottom of the bars.  To the remaining, add additional generous pinch of cardamom and 1/4 cup sweetened coconut.  After 15 minutes of baking, lightly sprinkle the topping onto the bars and cook until golden brown.