2 cups powder sugar
500 gr Butter (4 sticks)
1 Tbl grated orange zest
4 cups self-rising flour*
1 cup freshly squeezed orange juice
1 cup Icing Sugar
1/2 cup orange juice
* 1 cup self-rising flour=
1 cup regular flour + 1.5 teas. baking powder + 1 teas. salt
Heat the oven to 170C/Gas 3. You will need a 30 cm cake tin with removable sides, lined with non-stick silicone paper or well-greased with butter.
Cream the butter and sugar well, until it is very pale and thick - this will take quite a while.
Add the eggs one by one, beating well after each addition, and the zest, if using. Add the flour all at once, and beat well, then slowly add the orange juice, until it is incorporated.
Pour the batter into the prepared cake tin, and bake for 1 hour and 10 minutes - or until an inserted skewer comes out clean (slow is best, so don' t be afraid to cook it longer. If it starts to brown too much on the top, cover loosely with a sheet of buttered kitchen foil.)
Leave the cake in the tin on a wire rack to cool, then gently remove the sides of the tin.
To make the icing, stir the orange juice into the icing sugar until you have the right spreading consistency, and apply with a palette knife, allowing the icing to drip down the sides of the cake. Leave the icing to set before cutting the cake into wedges or storing in an airtight container.