Preheat oven to 350°F
In a large bowl, mash banana.
Wisk in butter.
Add egg, vanilla, rum and sugar. Stir to combine.
Add flour then baking soda. Stir until just combined. Do not over mix.
Fold in nuts.
Grease and flour large loaf pan.
Pour mix into pan.
Bake for about an hour or until toothpick inserted into center comes out clean.
Let cool completely.
Meanwhile make the drizzle... wisk together all drizzle ingrredients.
When bread is cool. Run a knife along edges to loosen. And turn out onto serving dish.
Drizzle your ... drizzle.. all over bread letting it run down the edges too!
Top with crushed nuts for garnish if you like. (I didnt as i ran out)
Slice and serve!