In a medium bowl, combine the potatoes and 1/2 tablespoon oil.
In a separate small bowl, mix the ground cumin, ginger, fennel, paprika, chili powder and salt.
Add the spice mix to the potatoes and toss well to coat.
Transfer the potatoes to an aluminum foil and seal the packet.
Grill the potatoes in foil for about 15-20 minutes (or until just tender).
Transfer the potatoes to a serving bowl and drizzle with the remaining 1 1/2 tablespoons oil.