Place bamboo skewers in a shallow bowl with water to soak.
Combine steak cubes, peppers and onions in a large bowl.
Add cumin, chili powder, paprika, cayenne pepper, salt, pepper and oil; mix well.
Remove skewers from water. Thread the steak and veggies onto the skewers.
Preheat grill to 425˚F(220˚C). Brush grill grates with oil. Place kabobs on the grill.
Cook for 8 to 10 minutes, flipping once, until the internal temperature of steak is 130-140˚F, depending on your preference.
Serve with chimichurri on the side.