Preheat and prep: Heat your oven to 375°F (190°C).
Lightly grease a 9x13-inch baking dish.
Sauté aromatics: Warm oil in a skillet over medium heat. Add onion and cook until translucent, about 4–5 minutes. Stir in garlic and cook 30 seconds, until fragrant.
Mix the chicken filling: In a large bowl, combine shredded chicken, sautéed onions and garlic, green chiles, cream cheese, chili powder, cumin, smoked paprika, and half the enchilada sauce.
Season with salt and pepper. Mix until creamy and evenly coated.
Layer the base: Spread a thin layer of enchilada sauce on the bottom of the baking dish to prevent sticking.
Add the low-carb “tortillas”: Arrange a layer of cauliflower or low-carb tortillas (or thin zucchini slices) to cover the bottom. Don’t worry if they overlap slightly.
Build the casserole: Spoon half the chicken mixture over the tortillas.
Sprinkle with one-third of the cheese. Add another layer of tortillas, the remaining chicken mixture, and another third of the cheese.
Top and sauce: Finish with a final layer of tortillas, pour the remaining enchilada sauce over the top, and scatter the last of the cheese.
Bake: Cover the dish loosely with foil and bake for 20 minutes. Remove foil and bake another 10–15 minutes, until the cheese is bubbly and golden at the edges.
Rest and garnish: Let it rest for 10 minutes to set.
Top with chopped cilantro and your choice of sour cream, avocado, jalapeños, or green onions.
Serve: Slice into squares and serve with lime wedges for a fresh squeeze on top.