Preheat oven to 350 degrees. (175 degree Celsius / 180 degree Celsius)
Butter an 8-inch round cake pan.
Stir flour, 1/2 cup plus 2 tablespoons sugar, the baking powder, baking soda, salt, yogurt, oil, orange zest and juice, egg, and vanilla in a bowl.
Pour into pan.
Bake until a cake tester comes out clean, about 25 minutes.
Let cool on a wire rack.
Place zest strips in a bowl.
Stir in segments and remaining tablespoon sugar.
Garnish cake with some segments; serve with the rest.
Dust with confectioners' sugar.
