Lightly grease 7" cake pan or springform pan with non-stick cooking spray or vegetable oil.
In a large bowl, mix together hash browns, soup, sour cream, onion powder, garlic powder, salt, pepper and 1 cup of cheese. Add sliced sausage and stir to combine. Scrape mixture into prepared pan. Sprinkle with remaining shredded cheese. Garnish with reserved sausage slices on top of cheese.
Tear off 12-inch piece of aluminum foil. Spray one side of foil with cooking spray to prevent sticking and cover top of pan with foil, sprayed side down. *if using springform pan, tear off 20-inch piece of foil, spray one side with non-stick cooking spray and wrap entire pan in foil, covering across the top of casserole, to prevent leaks and water getting into pan during cooking.
Add trivet to bottom of Instant Pot insert and pour in 1 cup of water. Place foil-wrapped pan into a silicon sling. Lower the sling with the pan into the Instant Pot insert and place on the trivet. Close lid and set the pressure valve to seal (if needed). Select HIGH pressure and set to 35 minutes.
When pressure cooking is done, allow a 10 minute natural release. Turn knob to venting position to remove any remaining steam. Open lid and carefully lift sling from Instant pot. Remove the foil from the pan. Allow to cool 10 minutes before cutting and serving.
Optional - Pressure cook according to instructions. Set oven broiler to HIGH. Place pan (without foil) in oven and broil for 2-3 minutes until sausage is crispy around the edges and cheese is starting to brown. Remove from broiler and cool 5 minutes before serving.