Preheat oven to 400 F. Line a baking sheet with parchment paper. Puncture the sweet potatoes with a fork several times and place them on the prepared baking sheet. Bake for 1 hour or until a knife can easily slice into the center. Remove from the oven and let cool for a few minutes. Reduce the oven heat to 350 F.
About 5 minutes before it's time for your sweet potatoes to come out of the oven, start your oatmeal. Combine the rest of the ingredients, except for the yogurt, in a medium pot. Bring to a boil over medium heat and then reduce the heat to a simmer. Let simmer for 10 minutes or until thickened.
Once the sweet potatoes are cool enough to touch, slice them in half and gently scoop out the flesh, keeping the skins intact. If needed, mash the sweet potato a flesh until it is in small chunks. Add the sweet potato to the oatmeal and stir to combine. Taste and add more sweetener or salt if necessary.
Divide the oatmeal mixture amongst the 4 potato "cups" until each has a heaping mound of oatmeal. Return to the oven and bake for 15 more minutes.
Remove from the oven and serve immediately, topped with yogurt and more maple syrup.
Enjoy!