Prep the potatoes: Wash and dry the potatoes. Cut into 1/2-inch cubes so they cook evenly.
Smaller pieces mean crisper edges.
Season: In a large bowl, toss the potatoes with olive oil, garlic powder, onion powder, smoked paprika, thyme, salt, and pepper until evenly coated.
Preheat the air fryer: Set to 400°F (200°C) for 3–5 minutes. A hot basket helps the potatoes crisp faster.
Air fry, batch if needed: Add potatoes in a single layer. Cook for 14–18 minutes, shaking the basket halfway.
Cook until deeply golden and tender inside. If your basket is small, cook in two batches for best results.
Make the ranch: While potatoes cook, whisk Greek yogurt, mayonnaise, lemon juice, garlic powder, onion powder, dill, parsley, and a splash of milk or water. Season with salt and pepper.
Adjust thickness to your liking.
Taste and finish: Check a potato for doneness and seasoning. Add a pinch more salt if needed. Toss with chopped chives or green onions.
Serve: Plate the potatoes hot with a side of Greek yogurt ranch.
Sprinkle with flaky salt for a final pop.