First, preheat oven to 350ºF and spray a standard bread pan with nonstick cooking spray.
Next, place dry ingredients in a medium bowl and whisk to combine. Set aside.
In a large bowl, mash 3 medium ripe bananas with a fork until they’re mostly pureed. You should get about a cup of mashed banana. Then crack in eggs and whisk to combine. Add maple syrup, Greek yogurt, vanilla, melted butter, and almond milk and whisk again.
Slowly add dry ingredients to wet and mix with a wooden spoon.
Transfer half of the batter into the bread pan and drizzle on half of the cinnamon mixture and use a knife or toothpick to swirl it in. Then, add the rest of the batter to the pan and then drizzle on the rest of the cinnamon mixture and swirl it in with a knife.
Bake at 350ºF for 25 minutes. Remove from oven and cover with a tented piece of tin foil. Then, bake for an additional 20-25 minutes or until a toothpick comes out clean.
Let cool for 10-15 minutes and then remove from pan to finish cooling on a cooling rack.