Combine shortening, sugar and vanilla. Beat till fluffy using an electric mixer. Add eggs and beat till combined.
Stir together flour and baking powder; add to egg mixture. Beat just till combined.
Divide batter. To one half add chocolate and nuts. To the other half add the crushed pineapple.
In greased 13x9x2" baking pan, alternate small spoonfuls of chocolate and pineapple batters.
Bake 350° 23-25 minutes
Cool and cut into bars.
Recipe submitted by Dobie on 7/7/00