Preheat oven to 400°F (200°C).
Prick sweet potatoes several times with a fork and rub skins with olive oil and a pinch of salt.
Place sweet potatoes on a parchment-lined baking sheet and roast for 45 to 50 minutes until soft.
While potatoes roast, heat a skillet over medium-high heat and add ground turkey.
Cook turkey until browned and fully cooked, breaking it into small crumbles.
Stir in chili powder, cumin, garlic powder, salt, pepper, and black beans; cook for 3 minutes to incorporate flavors.
Remove potatoes from oven and slice in half lengthwise once cool enough to handle.
Scoop out approximately half of the potato flesh, leaving a 1/4-inch thick shell; fold the scooped flesh into the turkey and bean mixture.
Spoon the turkey mixture back into the sweet potato shells and top with shredded cheddar cheese.
Return to oven for 5 to 7 minutes until cheese is melted and bubbly.
Garnish each boat with a dollop of Greek yogurt and chopped cilantro before serving.