Preheat oven to 350-f degrees. (See notes above for high altitude baking) Line a loaf pan with parchment and set aside. I recommend having the sides of the parchment longer so you can use them to pull the bread out of the pan easily.
In a large bowl mix bananas, butter, sugar, egg, vanilla, baking soda, salt and flour until just incorporated. Do not over mix. Spread 1/2 of the mixture into the bottom of the loaf pan.
To make the cinnamon swirl: Mix the cinnamon and sugar in a small bowl and sprinkle a little more than half on top of the banana mixture in loaf pan.
To make the cream cheese center: In a small bowl beat the cream cheese, sugar, and egg until smooth. Spread on top of the cinnamon sugar mixture.
Spread remaining banana bread batter on top of the cream cheese mixture. Sprinkle with remaining cinnamon sugar. Bake for 50-60 minutes or until toothpick comes out clean when inserted. Let cool for about 30 minutes and remove from the pan. I kept leftovers in the fridge and it takes just as wonderful chilled.
Notes
Adapted from The Recipe CriticNotes: For high altitude banana bread baking I lower the temperature to 325-f degrees and bake for about 15 to 20 minutes longer. I draped foil on top for the last 20 minutes of baking. The reason being is that all these changes prevent the banana bread from burning. My bread could have used an extra 5 minutes on top of what I baked it for, but it was very close. Every oven is a little different so please use whichever temperature and time works best in your experience. If in doubt, keep checking with a toothpick to see if the center is baked all the way through and drape foil over the top if it is getting too brown.