Peel the potato and microwave for 5 minutes to soften. Carefully shred using a box grater. (If using frozen hash browns, thaw completely and squeeze out excess moisture.)

In a mixing bowl, combine shredded potato, cream cheese, shredded cheese, chopped green chile, minced garlic, and onion if using. Season with garlic salt and black pepper.

Shape the mixture into small, slightly flattened cakes or “nests.” Place them on a plate or tray and freeze for 10 minutes to make them easier to handle.

Heat a skillet with a thin layer of oil over medium heat. Fry the potato cakes for 3–4 minutes per side until golden brown and crispy. Transfer to a paper towel-lined plate to drain excess oil.

In a small bowl, mix sour cream with chopped green chile and black pepper. Chill until ready to serve.

Serve potato cakes hot with the cool, creamy green chile sour cream for dipping.