Stir in shredded cheese, hash browns, cooked sausage, onion, and green bell pepper until well combined.
Season the mixture with salt and black pepper.
Grease the pressure cooker insert with melted butter.
Pour the mixture into the prepared pressure cooker insert and spread evenly.
Seal the pressure cooker and cook on high pressure for 30 minutes.
Allow pressure to release naturally for 10 minutes, then quick-release remaining pressure.
Carefully remove the insert and let the casserole rest for 5 minutes before serving.
Slice and serve warm, enjoy your hearty breakfast casserole!
Notes
This casserole is perfect for breakfast or brunch and can be prepared the night before. Use your favorite breakfast sausage or substitute with bacon or ham for a different twist.