3/4 stick (6 tbsp.) cold unsalted butter cut into bits
1/3 c. firmly packed light brown sugar
1 c. plus 3 tbsp. all purpose flour
1/2 c. finely ground walnuts
2 lg. eggs
1 c. granulated sugar
2 tbsp. fresh lemon juice
2 tsp. grated lemon rind
1/2 tsp. double acting baking powder
1 tbsp. confectioners' sugar or to taste

In a bowl blend the butter, the brown sugar, 1 cup of the flour, and the walnuts until the mixture resembles coarse meal. Press all but 1/2 cup of the mixture evenly into the bottom of a 9 inch square baking pan and bake the crust in a preheated moderate oven (350 degrees) for 15 to 20 minutes, or until it is golden around the edges.

In a bowl beat the eggs lightly and stir in the granulated sugar, the remaining 3 tablespoons flour, the lemon juice, the lemon rind, and the baking powder. Pour the mixture over the baked crust, sprinkle it evenly with the remaining 1/2 cup walnut mixture, and bake the dessert in the moderately heated 350 degree oven for about 20 minutes. Let set.