Preheat your oven to 400 degrees F.
In a medium bowl, toss the squash a tablespoon or two of olive oil and a dash of salt and black pepper. Pour the mixture onto a large baking sheet that has been lined with foil. Place it in the oven and roast the squash for about 40 minutes, or until tender. Remove from heat and set aside to cool slightly. Reduce the heat to 350 degrees F.
To a large skillet, add 2 tablespoons of olive oil. Heat over medium heat and add the onion. Cook until tender, about 5 minutes. Add the green chilies, chili powder, cumin and garlic powder. Cook for about 3 minutes or until the spices are fragrant. Stir in the green enchilada sauce and heavy cream. Bring to a gentle simmer and then stir in the cream cheese. Stir until the cheese has completely melted. Remove from heat and fold in the turkey and butternut squash. Take about half of the Monterey jack and cheddar cheese, and fold them in as well.
In a large baking dish, add about 1 cup of the red enchilada sauce. Spoon a small amount of the turkey mixture into each flour tortilla and roll up. Place them seam side down in the baking dish. Pour the remaining 1 cup of red enchilada sauce on top and any remaining filling. Top with remaining cheeses and place in the oven.
Bake the enchiladas for about 30 minutes or until melty. Remove from heat and top with desired toppings such as avocado, sour cream and cilantro. Enjoy!