Fill Instant Pot insert with water.
Switch Instant Pot to Sauté mode normal heat for 30 minutes with lid off. Add more time as needed.
Add miso paste to water, stir, and wait until the soup base begins to boil.
While soup base is heating up, prepare Hot Pot Ingredients.
Wash and chop mushrooms.
Wash fresh spinach.
Collect ramen noodles.
Slice extra firm tofu into desired shape and size.
Cut acorn squash in half, then proceed by chopping one half into roughly 2x1x1 inch chunks.
Slice onions into ribbons.
When the Instant Pot Hot Pot miso soup base has started boiling, gently place a few of each of the ingredients into the Instant Pot.
Wait a few minutes for ingredients to cook, and then fish them out using a straining ladle.
Dip into soy sauce or tamari sauce and eat.
Alternatively, ladle out soup broth with cooked ingredients into a bowl and drink.
Repeat adding ingredients to Instant Pot until satiated.