Shred the zucchini and ground the walnuts.
In a bowl, beat the eggs, oil, and vanilla together.
Add the dry ingredients to the wet blend.
Fold in the zucchini and walnuts.
Prepare a cake pan with non-stick cooking spray. Pour the batter into the cake pan.
Cover the top of the pan with foil.
Pour 1 cup of water into the bottom of the Instant Pot. Place the spring form pan on top of the trivet and lower the trivet and pan into the bottom of the Instant Pot.
Cover the Instant Pot. Press the manual button and set the timer for 60 minutes on high pressure. Set the valve to sealing.
When the timer beeps move the valve to vent. Carefully remove the trivet and pan from the Instant Pot. Let the bread/cake sit for 10 minutes. Remove the foil and serve warm or cold.