Start by marinating the steak: toss the sliced beef with lime juice, cumin, chili powder, paprika, salt, and pepper. Let it sit for at least 30 minutes to absorb the flavors.
Heat your cast-iron skillet over high heat until it’s very hot; this creates a perfect sear. Add a tablespoon of olive oil and swirl to coat the pan.
Carefully add the marinated steak strips to the hot skillet, spreading them out in a single layer. Hear the sizzle and smell the rich aroma as they sear for about 2-3 minutes without moving them, developing a caramelized crust.
Flip the steak strips and cook for another 2 minutes until evenly browned and juicy inside. Remove them from the skillet and set aside to rest.
In the same hot skillet, add the sliced onions and peppers. Toss them quickly to coat in the flavorful drippings, and cook until the vegetables are charred in spots and softened, about 4-5 minutes. They should release fragrant vapors and develop slight charring.
While the vegetables cook, wrap the tortillas in a damp cloth and warm them in a dry skillet or microwave until soft and pliable, about 30 seconds.
Slice the rested steak into thin strips against the grain. Squeeze a little extra lime juice over the meat for brightness and toss everything together for a flavorful mix.
Serve the sizzling steak and charred vegetables on warm tortillas. Top with additional lime juice or your favorite garnishes, and enjoy the vibrant, smoky flavors.
