Preheat oven to 400 degrees. Melt 1 Tbsp ghee and brush on both sides of sliced sweet potato. Place on baking sheet. Season with salt and pepper. Bake for 10-12 minutes or until crisp.
Meanwhile, heat remaining 1 Tbsp ghee over medium heat. Add onion and cook for 2-3 minutes. Add garlic and cook for an additional 1-2 minutes.
Add ground beef and cook, stirring to crumble, until browned. Drain any liquid from the pan and return to medium heat. Remaining ingredients and bring to a boil. Reduce heat to low and simmer for 10 minutes. Remove dates.
Serve sloppy joe mixture over sliced sweet potatoes.