Par-boil potatoes in boiling water and salt in medium saucepan for 5 minutes. Drain. Return saucepan to still hot burner and shake back and forth to dry potatoes slightly.
Combine garlic salt, pepper, cumin, paprika and cayenne pepper.
Preheat lightly sprayed electric grill to high. Put potatoes into large bowl. Drizzle with olive oil. Toss well to coat evenly. Sprinkle seasoning mixture over potatoes while tossing, until well distributed. Place potatoes on grill. Cook for about 20 minutes, turning frequently, until potatoes are tender and crispy brown. Serves 4.