Preheat your oven to 350°F (177°C) and grease a 9×5-inch metal loaf pan.

In a medium bowl, whisk together the flour, baking soda, ground cinnamon, and salt.

In a large mixing bowl, cream together softened unsalted butter and granulated sugar until smooth and creamy.

Add eggs, mashed bananas, Greek yogurt, and vanilla extract to the butter-sugar mixture and mix well.

Gradually incorporate the dry mixture and stir gently until just combined.

In a small bowl, mix together granulated sugar and ground cinnamon for the swirl.

Pour half of the batter into the pan, sprinkle the cinnamon sugar mixture, then add the remaining batter and swirl with a knife.

Bake for 55–65 minutes or until a toothpick comes out clean.

Let it cool in the pan for about 1 hour, then turn onto a wire rack to cool completely.

Prepare icing and drizzle over cooled bread using a spoon or piping bag.