Stir together flour, baking soda and salt.
In a separate bowl beat together sugar and butter until well blended.
Add eggs one at a time, beating well after each addition.
Add banana, yogurt and vanilla. Beat until blended.
Add flour mixture. Beat on low until just moist.
Spoon batter into prepared pan. Bake at least 50-60 minutes, until a toothpick come out clean. Cool 10 minutes before removing from pan.