For sauce: Combine all ingredients except beef in a small bowl and let sit for at least 30 minutes before using.
To prepare: Heat a grill or coals to high. Skewer beef pieces with a metal or wooden skewers. (If using wooden skewers, soak in water for at least 30 minutes before using). Place skewered meat over a baking sheet and pour half of the sauce over all, coating well. Grill over high heat brushing once or twice with remaining sauce. Grill until lightly charred on all sides. Remove from grill and serve.