Preheat the oven to 400°F (200°C).
Wash and poke holes in the sweet potatoes.
Bake the sweet potatoes for 45-60 minutes.
Remove baked sweet potatoes and allow to cool slightly.
Slice the sweet potatoes in half lengthwise and scoop out the flesh.
In a bowl, mix the sweet potato flesh with cranberries, diced apple, maple syrup, butter, cinnamon, and salt.
Spoon the mixture back into the potato skins.
Return the filled potatoes to the oven for an additional 15-20 minutes.
Serve warm, garnished if desired.