Let egg whites stand at room temperature for 30 minutes. In a large bowl, beat the egg yolks, sugar, applesauce and oil until well blended; beat in milk and extract. Combine the flours, coconut, baking powder and salt; gradually beat into egg yolk mixture until blended.
In another bowl, beat egg whites and cream of tartar until stiff peaks form; fold into batter.
Gently spoon into an ungreased 10-in. tube pan. Cut through batter with a knife to remove air pockets. Bake on the lowest oven rack at 325° for 65-75 minutes or until cake springs back when lightly touched. Immediately invert pan; cool completely, about 1 hour.
Run a knife around side and center tube of pan. Remove cake to a serving plate. Sprinkle with confectioners' sugar.