Preheat oven to 350F.
Peel the sweet potatoes.
Sprinkle sweet potatoes with salt, then wrap each in one or two Swiss chard leaves.
Place sweet potatoes seam side down on a baking sheet.
Bake for 40 minutes, or until fork tender.
Let cool for 10 minutes.
Slice sweet potatoes in half lengthwise.
Scoop out the inside of each half, placing the scooped potato onto the baking sheet.
To Make the Stuffing:
Preheat a sauté pan over medium heat.
Add butter, minced onion, and garlic to the pan. Sauté for 5 minutes until browned.
Add wild rice to the pan and stir.
Pour in vegetable broth, bouillon, crushed red pepper flakes, black pepper, garlic powder, and salt.
Bring to a boil, then cover and simmer for 40 minutes, or until rice is tender.
Once the rice is cooked, dice the scooped-out sweet potato flesh.
Fluff the cooked rice with fresh mint, basil, and Parmesan cheese.
Season the stuffing with salt and pepper to taste.