In a small bowl, mix together the chili powder, oregano, cumin, garlic power, and salt.
Sprinkle half the seasoning mixture over each side of the steak.
Heat oil over medium heat. Then add onions, peppers, and the remaining seasonings.
Cook until onions are soft, about 3–4 minutes.
Push the veggies to one side of the skillet, then add the steak and cook until desired done-ness (about 5–6 minutes each side).
Once the steak has been cooked, remove the pan from the heat and allow the steak to rest at least 5 minutes before slicing. Toss the steak slices with the peppers and onions, and serve.
Notes
You can swap the peppers and onions for veggies of your choice. Mushrooms and zucchini also work well!