1Remove pork medallions from the refrigerator 30 minutes before cooking to bring to room temperature. Pat dry with paper towels.
2If using a whole tenderloin instead of pre-cut medallions, slice into medallions about 2-3 cm (1 inch) thick.
3In a bowl, mix medallions with olive oil, minced garlic, dried thyme, dried rosemary, salt, and pepper. Toss well to coat evenly.
4Slice mushrooms. In another bowl, toss with melted butter and a pinch of salt and pepper.
5Preheat air fryer to 200°C (400°F).
6Place pork medallions in the air fryer basket. Scatter mushrooms around them (or on top if basket is small). Cook for 8-10 minutes.
7Halfway through cooking, shake mushrooms and flip medallions for even browning.
8Transfer cooked medallions to a warm plate, cover loosely with foil, and let rest for 5 minutes. This redistributes juices, keeping the meat tender.
9Return mushrooms to the air fryer and cook for another 2 minutes.