Whisk the eggs and feta cheese.
Add in the peppers, onions, spinach, salt, and pepper and mix to combine.
Spray the silicone molds with nonstick cooking spray.
Fill the molds with 1/4 cup of the egg mixture until each impression is filled about 3/4 of the way full.
Add 1 cup of water to the instant pot. Transfer the egg mold to the wire rack in the instant pot.
Place an 8" round piece of parchment paper on top of the egg mold to capture condensation drops.
Secure the lid on the pressure cooker. Set the pressure regulator to "sealing" mode. Select the "Manual" program and adjust the time to 8 minutes. If you are making a double batch, you can increase to 10 minutes.
The pressure cooker takes about 12 minutes to come to pressure, then 8 minutes of cooking under full pressure.
When the timer goes off, allow the pressure to release naturally for 5 minutes, (which means don't touch it for 5 minutes).
After 5 minutes, quickly release the remaining pressure by adjusting the pressure regulator knob to "venting". I always place a kitchen towel over the quick pressure release.
Remove the egg bites from the Instant Pot using ovenproof mitts. Remove the parchment paper, then place a small plate over the egg mold and flip the mold and plate to remove the egg bites from the mold.
Serve warm