Salsa, additional cheese, sour cream etc for serving
Grease a 7-inch diameter casserole dish or souffle dish (you can also use a springform pan but it may come through the bottom a little as it cooks).
Turn the Instant Pot onto the sauté function and add the avocado oil. Once hot, add the bulk sausage and break it up with a wooden spoon. Cook about 4 minutes until most of the pink is gone.
Add the grated broccoli stalks, garlic, and salt and pepper. Continue to cook another 2 minutes until the broccoli is tender. Transfer the mixture to the prepared baking dish.
In a medium bowl, whisk together the eggs and cream until well combined. Stir in the cheese and the green onion. Pour over the sausage mixture in the pan. Cover the dish tightly with aluminum foil (if using a springform pan, wrap the bottom in foil as well).
Pour 1 cup of water into the bottom of the Instant Pot and add the trivet. Place the dish on top of the trivet and lock the lid. Make sure the vent is closed. Set the cooker to manual pressure for 35 minutes.
When the cooking cycle is complete, let the pressure release naturally for 10 minutes. Then vent until all the pressure is gone. Remove the dish from the Instant Pot.
Top the casserole with the thinly sliced avocado before serving. Top with any other toppings you desire.