Marble cake with orange and cinnamon

Ingredients:

3 eggs
1 orange
1 cup sugar
about 1/3 cup milk
3/4 cup oil
3 cups flour
10 g baking powder
1 teaspoon vanilla extract
2 teaspoons cinnamon
1/2 cup ground hazelnuts
2 tablespoons cocoa powder
Pinch of salt

Directions:

• Set the oven to 180 C.
• Grate the zest of the orange and mix it into the sugar in a mixing bowl.
• Add the egg whites and beat until fluffy and white.
• Squeeze the orange into a cup, fill the rest with the milk and combine with the mixture.
• In a seperate bowl, combine the flour, vanilla, cinnamon and baking powder. Add the dry ingredients to the wet ingredients and mix thoroughly.
• Add the hazelnuts and mix.
• Transfer 1/3 of the mixture into the other bowl and add the cocoa to it.
• Pour both mixtures into a greased and floured baking pan, in such a way that they will create a pattern.
• Bake about 30 minutes, or until a toothpick comes out clear.
• After taking the cake out of the oven, you may add powdered sugar or pour some orange juice on it.

Enjoy :)