Preparation time: 20 minutes
Baking time: 40-45 minutes
 

1. Preheat the oven to 180° C (350° F).
2. Butter and flour a high-sided cake pan.
3. Wash and scrub the orange, grate the zest and extract the juice.
4. Separate the whites and yolks of the eggs. Place the yolks in a bowl with the sugar and whisk until pale and the mixture drops from the whisk in a ribbon.
5. Slowly whisk in the oil in a thin stream (as in making mayonnaise).
6. Add the grated orange zest, orange juice, and then the yogurt and the flour sifted with the baking powder. Mix together until smooth and evenly combined.
7. Beat the egg whites to stiff peaks and fold gently into the batter.
8. Pour into the prepared cake pan.
9. Place on the middle rack of a preheated 180° C (350° F) oven and bake for 20 minutes; reduce the heat to 160° C (325° F) and bake another 20-25 minutes.
10. Remove from the oven and turn out onto a rack to cool.
11. Just before serving, decorate with decorative picks and multicolored candies.