Beat egg yolks until light. Add sugar and beat again. Add dates and nuts; blend. Mixture will become very stiff. Sift together flour and baking powder into mixture, blend. It will become very dry and crumbly.
In separate bowl, beat egg whites until stiff and fold into mixture. Do not beat. Pour into 8 x 8 inch pan or microwave dish and bake at 325 degrees for 1/2 hour or microwave 20 minutes at 40% power, then 30 seconds at 100% power. Let cool.
This part of the cake can be made in advance. To build - scoop out cake onto large plate. Entirely messing it up. Peel and slice bananas and drain fruit. Layer and form into mound or any shape you like. Frost with generous amounts of Cool Whip or whipped cream. Garnish for whatever the occasion.
