1. Heat oven to 375 degrees. Coat a 13 x 9 x 2-inch baking dish with nonstick cooking spray.
2. Coat a 12-inch nonstick skillet with nonstick spray and place over medium heat. Crumble in ground turkey and add zucchini and onion. Cook until turkey is no longer pink and most of the liquid has evaporated, 10 minutes. Season with 1/2 tsp of the salt, the oregano, 1/4 tsp of the pepper and the cumin.
3. Meanwhile, combine salsa, half-and-half and remaining 1/4 tsp each of the salt and pepper in a blender and pulse until smooth. Stir 3/4 cup of the sauce into skillet and heat through. Remove from heat and stir in 1/4 cup of the cheese.
4. Pour 2/3 cup of the sauce over prepared dish, tilting to coat bottom. Heat a small nonstick skillet over medium-high heat and add 1 tortilla. Heat, flipping, 20 seconds. Transfer to a work surface and spoon 1/4 cup of the turkey mixture down center. Roll up to enclose filling and transfer, seam side down, to prepared dish. Repeat with remaining tortillas and filling.
5. Pour remaining sauce over enchiladas and top with remaining 3/4 cup cheese. Bake at 375 degrees for 25 minutes. Serve warm. Garnish with cilantro, if desired.