Boil the potatoes: Add the peeled, chopped potatoes to a pot of salted cold water. Bring to a boil and cook until fork-tender, about 12–15 minutes.
Drain well.
Mash until smooth: Return the potatoes to the warm pot to steam off extra moisture. Mash with butter and milk until smooth and fluffy. You want a slightly firm mash, not too loose.
Season the mixture: Stir in salt, pepper, garlic powder, onion powder, and herbs if using.
Mix in the grated cheese and 1 beaten egg. Taste and adjust seasoning.
Chill the mash: Spread the mixture in a shallow dish and refrigerate for 30–45 minutes. This firms it up, making shaping easier.
Set up breading station: Put flour in one bowl, beaten eggs in a second, and breadcrumbs in a third.
Lightly season the breadcrumbs with salt and pepper.
Shape the croquettes: Scoop about 2 tablespoons of the potato mixture and roll into a cylinder or small oval. You should get 16–20 croquettes.
Bread the croquettes: Dredge each one in flour, dip in egg, then roll in breadcrumbs until fully coated. Press gently so the crumbs adhere.
Preheat the air fryer: Set it to 380°F (193°C) for 3–5 minutes.
Lightly spray the basket with oil.
Air fry in batches: Arrange croquettes in a single layer without touching. Lightly mist the tops with oil. Cook for 10–12 minutes, turning halfway, until deep golden and crisp.
Thicker croquettes may need an extra 2–3 minutes.
Serve hot: Let them cool for 2–3 minutes to set, then serve with your favorite dips.