Heat a grill pan, skillet, or griddle with the oil over high heat.
Pat the steak dry. Mix all of the spices and coat the steak. Cook on each side for about 4-5 minutes. Remove the steak and slice perpendicular to the grain in thin slices.
Add the onion and pepper to the pan, reduce heat to medium. Cook for 3-4 minutes until the onion starts to go translucent.
Add the meat back in and cook for one more minute, tossing all of the ingredients together.
Serve over rice or in tacos and enjoy.