Pierce potatoes with a fork, and bake at 375° for 1 hour or until tender. Cool potatoes slightly.
Heat oil in a medium skillet over medium-low heat. Add onion, ginger, and garlic; cook 3 minutes. Add cumin, coriander, and pepper; cook 1 minute. Add 3/4 cup water and next 4 ingredients (through salt), stirring until smooth; bring to a simmer. Cook 2 minutes or until thick.
Split potatoes lengthwise, cutting to, but not through, other side. Spoon about 1/4 cup sauce into each potato. Top each serving with 1 teaspoon cilantro.