Preheat oven to 350 degrees.

Coat tube pan with butter and flour

In a separate bowl sift together flour and baking powder

Beat yogurt, eggs, sugar and oil until blended with wooden spoon or mixer

Add flour/baking powder mixture

Continue beating until bubbles form, do not over beat

Pour batter into prepared pan and place in oven for 40 to 45 minutes (test with toothpick)

Allow to cool slightly in pan before removing.