Preheat oven to 180 degrees C. Lightly spoon flour into dry measuring cups, level with a knife.
Combine flour, baking soda, and salt, stirring with a whisk. Place granulated sugar and butter in a large bowl, beat with a mixer at medium speed until well blended. Add eggs, 1 at a time, beating well after each addition. Add banana, yogurt, rum, and vanilla, beat until blended. Add flour mixture, beat at low speed just until moist. Stir in 1/2 cup coconut.
Spoon better in 9x5 inch loaf pan coated with cooking spray, sprinkle with 1 tablespoon coconut.
Bake at 180 degrees C for 1 hour or until a wooden pick inserted in centre comes out clean. Cool in pan 10 minutes on a wire rack, remove from pan.
Combine icing sugar and juice, stirring with a whisk, drizzle over warm bread. Cool completely on wire rack.