Combine oil, chococlate, and sugar. Add eggs one at a time, beating well after each addition. Add vanilla. Stir flour, baking powder and salt into oil mixture. Add nuts. Chill for several hours or overnight. Roll dough into balls by teaspoonfuls. Roll into confectioners' sugar. Place 2 inches apart on greased baking sheet. Bake at 350 degrees for 10 to 12 minutes. Do not overbake. Yields 6 to 7 dozen cookies.