Directions

1. Set pressure cooker to "sear", add oil, adjust time to 15 minutes, and press "start/stop". When hot, add chicken breasts. Add fresh ground black pepper. Sear meat, about 5 minutes per side. Remove chicken. Cube chicken into 1-to 2-inch pieces; set aside.

2. Add butter and melt then add onions, garlic, and mushrooms and cook until golden brown. Once golden, incorporate flour. Mix well. Add half & half, chicken stock, Parmesan cheese, and oregano. Return chicken to cooker. Add water.
3. Close and lock lid, set pressure cooker to "poultry", adjust tie to 5 minutes, and press "start/stop".
4. When done, quick release and make sure all pressure is released before opening lid. Carefully open lid, check seasoning and add salt and pepper, if needed. Add pasta and chopped arugula. Mix well. If sauce is too thick, add extra water. Serve.