Rinse apricots, cover with water, and boil 10 minutes. Drain, cool, and chop.
Grease an 8X8 metal baking pan. Line with a strip of parchment paper if desired.
Preheat oven to 350°F.
Mix butter, granulated sugar, and 1 cup of flour, until crumbly. Press into prepared pan.
Bake about 25 minutes, or until lightly browned.
Sift together 1/3 cup flour, baking powder, salt.
In a separate mixing bowl, or the bowl of a stand mixer, gradually beat the brown sugar into the eggs.
Add the flour mixture to the butter mixture, and mix well.
Stir in the vanilla, nuts, and apricots.
Spread the apricot mixture on top of the crust.
Bake 30 minutes, or until done.
Cool in pan, before cutting into bars and rolling in confectioner's sugar.