In a large mixing bowl, combine the flour, baking soda, and salt, stirring with a whisk to combine.
Using a hand mixer, in a large bowl, mix together the sugar and butter at medium speed until creamy. Add the eggs 1 at a time, beating well after each addition. Add the mashed bananas, yogurt, rum, and vanilla, mixing until well blended.
Add the dry ingredients to the wet ingredients and beat at low speed just until moist. Stir in ½ cup coconut. Spoon the batter into a prepared loaf pan coated with cooking spray and sprinkle the top of the batter with 1 tablespoon coconut.
Bake for 1 hour or until a wooden pick inserted in the center of the bread comes out clean. Cool 10 minutes in pan on a wire rack; remove from pan and place on wire rack for glazing.
For the glaze
In a small bowl, using a hand whisk, combine the powdered sugar and juice until smooth. Drizzle the over warm bread. Cool bread completely on wire rack.