In a small bowl stir together hoisin, honey, olive oil, and salt. Halve sweet potatoes. Brush the cut sides with 2 tablespoons of the hoisin mixture. Place potatoes, cut sides down, in baking pan lined with foil and coated with nonstick cooking spray. Roast at 425 degrees F for 25 to 30 minutes or until tender.
Add lime juice to remaining hoisin mixture; spoon over cooked sweet potatoes. Top with cashews and green onion. Serve with lime wedges.