If your flank steak isn’t already trimmed, slice off any excess fat. Sprinkle with salt, pepper, chili powder, and cumin, massaging the spices into the meat.

Slice the bell pepper and onion into thin strips.

Heat 2 tablespoons of olive oil in a large skillet over medium-high heat until shimmering.

Carefully add the seasoned flank steak to the hot pan. Sear for about 4-5 minutes on each side, aiming for medium-rare.

Remove the steak from the pan and let it rest for 5 minutes.

In the same pan, add the sliced onions and bell peppers, sautéing for 5-7 minutes until tender and lightly caramelized.

While the veggies are cooking, slice the rested steak against the grain into thin strips.

Return the steak to the pan, drizzle with lime juice, and combine everything until heated through.

Serve immediately in warm tortillas topped with your choice of toppings.