If you like your bread to have a delicate, uniform crumb, use a food processor or egg beaters to process the banana into a smooth puree. I prefer to mash my bananas with a fork, leaving them slightly chunky – you'll end up with small pockets of intense banana flavor throughout the bread. Adapted from The More than Occasional Baker
Bring the water to a boil in a small saucepan. Remove from heat and add the tea bags. Allow the tea to steep for 5 minutes, then discard the tea bags. Add the sugars and butter and return the pan to the heat. Cook until the butter and sugars have melted into a thick syrup, about 2 minutes. Let cool.
Combine the sour cream and baking soda in a large bowl. Let stand for 5 minutes. Stir in the cooled tea syrup and the eggs. Sift in the flour and fold gently to combine. Fold in the mashed bananas.
Pour the batter into two greased loaf pans. Sprinkle the tops with turbinado sugar.
Bake for 1 hour and 15 minutes, or until a toothpick inserted into the center of the bread comes out clean. Allow to cool completely before slicing.