Cut the zucchini in half, lengthwise. Using a small spoon or a melon baller scoop out the flesh.
Chop up the zucchini flesh and mushrooms. In a skillet add the tbsp of olive oil and heat. If you're using cooked shredded chicken, add zucchini flesh, mushrooms and chicken to the skillet together, otherwise add the chicken first and cook until no longer pink. To it add the chopped up zucchini flesh and mushrooms. Season with salt and pepper, cumin and oregano.
Spoon the chicken mixture into each zucchini boat, stuff them well, there shouldn't be any mixture left. Spoon some of the enchilada sauce over each zucchini, dividing the sauce equally. Sprinkle each zucchini with cheese.
Place zucchini on a baking sheet and cover with aluminum foil. Bake covered for about 30 to 40 minutes or until zucchini is cooked through.