Preheat the oven to 375F.
Dice the yams and place in casserole dishes. Sprinkle the salt over the yams.
Place the oil, mustard seeds, cumin seeds and curry leaves in a small skillet or sauce pan. Heat for 2 minutes.
After the spices are infused in the oil, place the oil and spices in the casserole dishes. Stir the yams until the oil and spices are evenly distributed over the yams.
Bake in the oven for 35 minutes, or until fork tender.