Preheat oven to 400°F. Line a baking sheet with parchment paper.
In a large bowl, combine sweet potatoes, olive oil, garlic powder, chipotle pepper, cumin, ginger, cinnamon, and salt. Mix until sweet potatoes are evenly coated.
Spread sweet potatoes onto the prepared baking sheet in a single layer and bake for 25 minutes, flipping once halfway through cooking.
Once sweet potatoes are tender, remove from oven and place in a large bowl.
Add milk, butter, and cilantro to the bowl. Mash until desired consistency is reached.
Garnish with feta cheese, if desired, and serve warm.
Interesting Facts
Sweet potatoes are a great source of vitamin A, vitamin C, and dietary fiber.
Chipotle peppers are a type of smoked jalapeno pepper.