Spray egg bite molds with olive oil baking spray.
Cut prosciutto slices in half, and lay each half slice inside a bite cup. Press up against the sides, and fold the tops back over the lip. Don’t worry if the meat splits into two pieces, just lay them both into the cup.
Into a glass measuring cup with a pour spout, put 4 eggs, salt, pepper, and onion powder. Add 1/4 cup shredded cheddar cheese and mix with a fork.Keep in mind that the prosciutto is salty on its own, and the instant pot tends to intensify salt flavor, so keep the added salt to a minimum. Roughly chop 1 cup of baby spinach leaves, and three broccolini florets.
Add them to the egg mixture as well, and mix with a fork.
Pour the egg and veggie mixture into the cups. I like to fill about half way up in each one, stirring with a fork in between, to make sure the veggies get distributed well into each bite.
Then use the remaining mixture to fill all the bites evenly. Make sure not to overfill them, since they will puff up a bit when cooking.
Fold the tops of the prosciutto over to cover the egg mixture.
Using a silicone cover or aluminum foil, cover the egg bite mold loosely.
Add 1 cup of water into the instant pot.
Put the egg bites onto the sling.
Lower into the pot.
Close the lid, set the steam release nozzle to the closed position, and set the instant pot to manual high setting for 10 minutes. Leave the pot to do a natural pressure release until the pin drops.
Carefully remove the lid and lift the sling out of the pot.
While still hot, pop the egg bites out of the molds. Serve immediately.