Mashed Sweet Potatoes with Caramelized Onions, Brie and Sage

Bahan-bahan (4 porsi)

• 3 medium orange flesh sweet potatoes, (peeled)
• 1 medium onion, (sliced thinly)
• 1 tablespoon olive oil
• ½ teaspoon granulated white sugar
• 1 tablespoon salted butter
• 4 ounces (about ½ cup) brie, (cut into pieces (rind removed))
• ¼ to ½ cup nonfat milk
• 1 tablespoon julienned fresh sage
• salt and freshly ground black pepper