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

In a medium bowl, whisk together the eggs, butter, milk, and vanilla.

Make a well in the center of the dry ingredients and mix in the wet ingredients, just until combined. The batter should still be lump with a few dry spots.

Fold in the mashed banana.

Grease a 7 inch push pan with oil and flour.

Pour the batter into the pan and gently place a paper towel over the pan.

Wrap the pan tightly with foil.

Pour 1 cup water in the bowl of your instant pot and place a trivet inside.

Create a foil sling with a long piece of foil and place inside the pot on top of the trivet.

Gently place the pan with the banana bread inside the instant pot, making sure the foil sling is sticking up on both sides.

Close the lid and set to sealing.

Set to manual - high pressure - 65 minutes.

Natural pressure release.

Gently remove the pan using the foil sling.

Remove the foil and paper towel. Use a clean paper towel to gently blot up in additional moisture that may have accumulated on top of the banana bread.