In a large mixing bowl, whisk together the eggs, half and half (or milk), salt and pepper. Stir in bread, cheese, spinach, and green onions.
Pour the mixture into the greased pan.
Put 1.5 cups of water into the Instant Pot. Place a steamer rack in the pot. Place the bread and egg mixture on the rack.
Close the lid. Press PRESSURE COOK and cook on HIGH PRESSURE for 15 minutes. Allow the pot to rest undisturbed for 10 minutes, and then release all remaining pressure.
Carefully remove the pan from the rack and ensure the strata is cooked through. You may need to use a paper towel to pat the top of the frittata dry. Allow it to cook a little from the residual heat before releasing the sides of the springform pan.
Serve and enjoy!
Tips and Tricks for Making this Spinach and Cheese Strata Recipe