Preheat the oven to 350°F. Line a 9x5-inch loaf pan with parchment paper so that it hangs over on the longer sides then grease the parchment paper with cooking spray.

In a large bowl, whisk together the flour, sugar, salt and baking soda.

In a separate medium bowl, whisk together the mashed bananas, eggs, buttermilk, melted butter and vanilla extract.

Add the wet ingredients to the dry ingredients and mix just until combined. Set the batter aside.

In a small bowl, whisk together the cream cheese, egg, sugar and flour.

Add ⅓ of the banana bread batter to the prepared loaf pan then alternately add dollops of the cream cheese filling and remaining banana bread batter to the pan. Using a knife, swirl together the mixture.

Bake the bread for 50 to 60 minutes until the top is set. If the bread is getting too dark around the edges, tent the pan with foil and continue baking.

Remove the bread from the oven and allow it to cool in the pan for 10 minutes before using the parchment paper overhangs to lift the bread out of the pan and onto a rack to cool completely. Slice and serve.