In a bowl, combine olive oil, chili powder, cumin, smoked paprika, garlic powder, onion powder, salt, and black pepper.

Place the flank steak in a resealable plastic bag or a shallow dish and pour the marinade over it. Let it sit for at least 15 minutes, or up to 4 hours in the fridge for deeper flavor.

Preheat your skillet over medium-high heat until it’s hot.

Remove the steak from the marinade and place it in the skillet. Cook for about 5-7 minutes on each side.

Transfer the cooked steak to a cutting board and let it rest for 5 minutes.

In the same skillet, add the sliced bell pepper and onion. Sauté for about 5 minutes until they are tender and slightly charred.

Using a sharp knife, slice the steak against the grain into thin strips.

Warm the tortillas in the skillet for a few seconds on each side. Fill each tortilla with steak, sautéed vegetables, and your favorite toppings.