Spray a 110x15 inch baking pan
with nonstick cooking spray.
Line the same pan with waxed paper and coat the paper with non stick cooking spray; set aside.
Combine the flour, baking soda, salt and baking powder. Set aside
In a separate mixing bowl, beat eggs for 5 minutes; add 1/2 cup sugar, banana, vanilla and lemon peel.
In a separate mixing bowl, beat egg whites on medium speed until soft peaks form. Then gradually beat in remaining sugar, a tablespoon at a time, at high speed until stiff peaks form.
Add flour mixture to banana mixture; mix gently until combined.
Fold in egg white mixture.
Spread into prepared pan. I find that to get it to spread evenly, picking up the pan, and sort of banging it down onto a counter can help.
Bake at 375 degrees for 10-12 minutes, until cake springs back when touched.
Cool 5 minutes in pan, on rack.
Dust a kitchen towel with confectioner sugar
Turn cake onto the dusted kitchen towel
Peel off waxed paper. Be careful when doing so.
Roll up cake in towel jelly-roll style, starting with a short side.
Cool completely on a wire rack.
Unroll cake after completely cooled, so you can fill it, and re-roll it.