Spray a roasting pan with cooking spray and preheat oven to 400 degrees.
Trim pork roast if necessary and place in center of roasting pan, fatty side down.
In separate small bowl combine olive oil, Kosher salt, rosemary, and minced garlic, then spread olive oil mixture evenly across the top of your roast.
Arrange potatoes, onion, mushrooms, and garlic cloves around pork roast.
Combine olive oil, pepper, Kosher salt, and rosemary, then drizzle onto potatoes and toss gently to coat.
Roast at 400 degrees for 45 minutes to one hour, or until pork reaches 145-160 degrees internal temperature (your preference).
Remove roast to cutting board and let it rest for 15 minutes before slicing.
A quick note on cooking times: I cooked my pork roast for an hour to 160 degrees with a meat thermometer, because MashupDad has concerns about pork and prefers his more well done. Per newer cooking guidelines and my own taste, I would have cooked it more like 45 minutes to 145 degrees internal temperature, but that’s personal preference. Start checking at 45 minutes and use your own judgment and taste.
Garlic Rosemary Pork Roast & Potatoes from Mashup Mom: https://www.mashupmom.com/garlic-rosemary-pork-roast-potatoes/