Preheat oven to 175°C. Grease and line a loaf pan. Place the raisins in a small bowl and cover with warm water, to soak.
Beat sugar, butter, vanilla bean paste, and rum essence together in a mixer on medium speed until well-blended (about 5 minutes). Add egg and egg white, and beat well.
Combine flour, baking powder, baking soda, and salt, and stir well. Add flour mixture to sugar mixture alternately with yogurt, beginning and ending with flour mixture. Drain the raisins, and fold them through.
Pour the batter into prepared pan. Bake for 1 hour or until a wooden pick inserted in middle comes out clean.
To prepare glaze, combine powdered sugar with water and vanilla. Spread over hot cake. Cool in pan 20 minutes on a wire rack. Then remove from pan and cool completely on wire rack.