Combine first 7 ingredients in a large bowl. Brush fish with 1 tablespoon oil; sprinkle spice rub over fish, then gently massage it in with your fingertips.
Brush grill rack or grill pan with remaining 1 tablespoon oil. Heat grill or grill pan to medium-high; add fish. Cook 3 to 4 minutes per side or until fish is just cooked through. (Do not try to turn fish until it lifts readily from the surface, which indicates the fish has been properly seared.)