Add one cup of water to the pot, followed by the steam rack. Place 4 eggs on the rack, then secure the lid, making sure the vent is closed.
Use the +/- keys and program the Instant Pot for 3 minutes for very soft eggs or up to 5 minutes for firmer eggs. When the time is up, quick-release the pressure.
Remove the eggs to a bowl filled with ice water for 5 minutes, then gently peel.
Mix soy sauce, rice wine and water in a 1 quart plastic bag. Put eggs in bag and seal, removing as much air as possible so eggs are covered with sauce. Allow to marinate 1 hour (or up to overnight in the refrigerator).
Remove rack and discard cooking water.
For Ramen Bowl
Add oil to the Instant Pot. Using the display panel select the SAUTE function and adjust to HIGH or MORE.
When oil gets hot add quartered onion to the pot and allow to cook, undisturbed, for 5-6 minutes until lightly charred.
Add mushrooms and cook and stir for 2 minutes. Add garlic and ginger and cook for an additional 1 minute.
Add warmed broth to the pot and deglaze by using a wooden spoon to scrape the brown bits from the bottom of the pot.
Add remaining Pot Mixture ingredients and stir to combine.
Turn the pot off by selecting CANCEL, then secure the lid, making sure the vent is closed.
Using the display panel select the MANUAL or PRESSURE COOK function*. Use the +/- keys and program the Instant Pot for 8 minutes.
When the time is up, let the pressure naturally release for 10 minutes, then quick-release the remaining pressure.
Carefully remove the meat from the pot to a cutting board and shred.
Add noodles to the broth mixture and cook according to package directions.
Add spinach and shredded chicken. Serve immediately with toppings of your choice.
*The MANUAL and PRESSURE COOK buttons are interchangeable.