Arrange the sweet potato slices in overlapping rows in an oiled shallow 2-quart casserole.
In a small bowl, combine the syrup, Earth Balance, juice, cinnamon, and salt. Pour evenly over the potatoes. Sprinkle the tarragon over the top.
Cover with lid or foil and bake, covered, for 25 to 30 minutes, or until the sweet potatoes are readily pierced with a fork, but are still firm.
Bake for 20 to 25 minutes longer, uncovered, or until glazed and golden around the edges. Cover and keep warm until needed, then serve from the casserole.