Mix the flour, baking soda, and salt in a big bowl.
Put the bananas in a medium bowl and use a potato masher or fork to mash them until they are extremely smooth.
Add the sugar, oil, sour cream, egg, and vanilla and whisk until everything is smooth.
Just blend the dry ingredients by folding them in. Avoid mixing too much.
If preferred, add walnuts and mix gently.
Fill a non-stick 6- 7″ round baking pan with batter, then put the pan into the air fryer basket. (Alternatively, you can use any air fryer-safe pan of a comparable size, or the square, tall-sided pan that came with your air fryer.)
A toothpick inserted in the center of the bread should come out clean after 33 to 37 minutes of baking at 310 degrees.
Before removing, let cool in the baking pan on a wire rack for at least 20 minutes.
