Marbled Egg-White Cake

Some time back, I've baked a  Yellow Butter Cake using just egg yolks and  now with a container full of egg whites sitting in my freezer for months, I've decided to try baking a cake with egg whites only.   This recipe has been adapted from here.

 

Ingredients:

1 cup egg whites
150g castor sugar
160g plain flour, sift
1/2 tsp cream of tartar
60g butter (melted and cooled)
1 tsp vanilla extract
50g dark chocolate, melted in the microwave

• Preheat oven to 160 deg C.  Grease a bundt pan and dust with flour.  Shake away excess flour.
• Beat egg whites until foamy and add in cream of tartar.  Continue whisking until soft peaks form.  Gradually add in sugar, beating until stiff and shiny.
• Gently fold in sifted flour and melted butter and vanilla extract.  Fold thoroughly.
• Pour half of the cake batter into a separate bowl and stir in melted chocolate.
• Spoon the batter into the prepared pan by alternating spoons of vanilla batter and chocolate batter.   Gently swirl together with a knife, taking care not to over mix.
• Bake for about 35 minutes or until cake is done.