Banana Chiffon Cake

2 cups all purpose flour

1 1/2 cup granulated sugar

1 Tbsp baking powder

1 tsp salt

1/2 cooking oil

7 egg yokes

1 cup mashed ripe banana

1 Tbsp lemon juice

1 Tbsp water

1 tsp vanilla

7 egg whites, room temperature

1/2 tsp cream of tartar

Sift first four ingredients into bowl. Make a well in the center. Measure next 6 ingredients into well. Don't beat yet. Set aside. Beat egg whites until frothy. Add cream of tartar. Beat until very stiff. Using same beaters, beat yoke flour mixture until smooth. Gently and gradually fold into egg whites. Turn into 10 inch ungreased tube pan. Bake in 320 degree Fahrenheit oven for 60 to 65 minutes until an inserted wooden pick comes out clean. Invert pan until cake has cooled.