In a mixing bowl, combine the cold roasted garlic instant mashed potatoes, well-drained sauerkraut, shredded Swiss cheese, chopped corned beef, one large egg, salt, pepper, and parsley. Stir everything together until fully blended.

Using your hands, form the mixture into cylindrical or ball shapes, about 1.5 tablespoons each. If the mixture feels too loose, chill it in the refrigerator for 20-30 minutes to firm it up.

Create a dredging station with three bowls: the first for all-purpose flour seasoned with salt and pepper, the second for a beaten egg, and the third for panko breadcrumbs, also seasoned.

One by one, coat each croquette in the flour, then dip it in the egg, and finally roll it in the breadcrumbs, ensuring an even coat for maximum crispiness.

Place the coated croquettes in the air fryer basket in a single layer without overcrowding. Lightly spray them with olive oil to encourage a golden finish.

Set the air fryer to 400°F and cook for 8-10 minutes, flipping them halfway through until they are golden brown and crispy on the outside.

Once cooked, serve the croquettes hot with Thousand Island dressing for dipping.