Preheat the oven to 425º and spray a baking sheet with olive oil cooking spray.
Prepare sweet potatoes by poking them with a fork 4-5 times. Spray or rub the sweet potatoes with olive oil cooking spray and season with salt and pepper. Place in the oven and bake for 50-60 minutes.
While the potatoes are roasting, heat a large skillet over medium/high heat. Add olive oil. When olive oil is fragrant, add onion and cook for 2-3 minutes. Add ground turkey and garlic to the skillet and cook over medium heat for 5 minutes or until browned. Season with salt and pepper, and remove from heat.
Next, place all ingredients for the enchilada sauce into a medium saucepan. Cook over medium heat and bring to a boil. Turn heat to low and let simmer for 10 minutes. Remove from heat.
Remove sweet potatoes from the oven and let cool. Once the sweet potatoes are cool enough, cut in half (hotdog style) and carefully remove the inside of the sweet potato, leaving a small layer of sweet potato to keep the skin intact.
Place 2 cups of the sweet potato flesh into a large bowl and mash with a fork. Add ground turkey, black beans, chopped cilantro, and 1/4 cup of enchilada sauce and mix well.
Scoop sweet potato mixture into the sweet potato skins. Smother sweet potato halves with more enchilada sauce and bake at 425º for another 10-15 minutes.
Remove from oven, sprinkle with optional toppings and enjoy!