Preheat the oven to 400°F. Line a baking sheet with parchment paper and set it aside.
Poke the sweet potatoes several times with a fork and rub them with 1 tablespoon of the olive oil. Place them on the prepared baking sheet and bake for 50 minutes, or until easily pierced with a skewer.
Near the end of the potato cooking time, heat a large skillet over medium heat. Add the remaining 1 tablespoon olive oil, then add the ground turkey and cook while breaking it apart until browned.
Drain any excess grease. Add the taco seasoning and tomato sauce, simmer for 5 minutes, then stir in the black beans.
Slice the cooked sweet potatoes down the middle and push the ends toward each other to open them. Gently mash the insides with a fork, top with the turkey and bean mixture, and add taco toppings if desired.
Notes
Optional taco toppings are not required for the primary recipe.