Preheat oven to 350°, In a small bowl, combine flour, confectioners' sugar and lemon peel; cut in butter until crumbly. Press onto the bottom and 1/2 in. up the sides of a greased 9-in. springform pan. Bake 10-15 minutes or until crust is lightly browned. Cool on a wire rack.
In a small bowl, beat eggs, sugar and lemon juice until thick and lemon-colored. Beat in flour, baking powder and lemon peel until blended. Pour into crust. Bake 20-25 minutes or until set.
For topping, in a small bowl, combine flour and brown sugar; cut in butter until crumbly. Stir in pecans. Sprinkle over filling. Bake 20-25 minutes or until a toothpick inserted near the center comes out clean. Cool completely on a wire rack. Remove sides of pan. Dust with confectioners' sugar. Refrigerate leftovers. Yield: 12 servings.