I make these each Christmas.

CRUST:

1/2 c. sweet butter
1/3 c. flour
1/4 c. sugar

FILLING:

2 eggs
3/4 c. sugar
2 tbsp. flour
1/4 tsp. baking powder
3 tbsp. lemon or lime juice

In small bowl, combine crust ingredients. Mix at low speed until blended. Pat into ungreased 8 inch square pan and bake at 350 degrees for 15 to 20 minutes, or until brown on the edge. Meanwhile prepare filling. Pour filling over partially baked crust. Bake 18 to 20 minutes or until set. Sprinkle with confectioners' sugar and cool. Cut into squares.