Pour sugar mixture evenly over sweet potatoes in the baking dish.
Cover with lightly greased (cooking spray) aluminum foil.
Bake, covered, in the preheated oven, about 40 minutes. Uncover and gently stir potato mixture. Bake, uncovered, until potatoes are tender, 25 to 30 more minutes.
Transfer potatoes to a serving bowl with a slotted spoon; pour syrup over potatoes. Serve immediately.
Notes
For best results, use fresh sweet potatoes, not canned. Canned ones tend to fall apart during baking and won’t hold up in the syrup.
Slice the sweet potatoes evenly. Cutting the sweet potatoes into uniform ½-inch rounds helps them cook at the same rate and keeps the texture just right.
Storage: Leftovers can be refrigerated in an airtight container for up to 4 days or frozen for up to 2 months. Reheat gently in the oven or on the stovetop until warmed through.