Since cotija is saltier and has a stronger flavor than queso fresco, consider using less of the former when the recipe calls for the latter. Or if you're using queso fresco in place of cotija ...

Pour green enchilada sauce over the top, then sprinkle queso fresco. Bake at 375F for 20 minutes. 3) Make Avocado Crema: Blend avocado, sour cream, lime juice, and cilantro until smooth.