In a large bowl or zip-top bag, mix all marinade ingredients. Add steak and toss to coat thoroughly. Refrigerate, turning occasionally, for at least 1 hour (4–6 hours is ideal).

💡 Don’t over-marinate skirt/flank steak more than 8 hours – it can get mushy.

Heat a cast iron skillet over high heat until very hot. Add 1 tablespoon oil, then peppers and onions. Season with salt and pepper. Sear without stirring too much — you want that char! Cook until vegetables are softened and blistered (about 8–10 minutes). Remove and set aside, keep warm.

Remove steak from marinade and pat dry (very important for a good sear). Heat a clean skillet or grill over high heat (cast iron preferred). Sear steak for 3–5 minutes per side, depending on thickness, for medium-rare. Rest for 5–10 minutes on a board, then slice thinly against the grain.

While steak rests, return veggies to skillet and reheat. Slice steak and nestle on top of hot veggies in the cast iron skillet. For that classic restaurant-style "sizzle," heat an extra teaspoon of oil in a separate pan and drizzle it over just before serving (optional).

Bring sizzling skillet to the table. Serve with warm tortillas and bowls of sour cream, guacamole, pico de gallo, cheese, and lime wedges. Let everyone build their own fajitas.

🔥 Tips: Skirt steak is king: More flavorful and tender when sliced properly. Cast iron is key: It retains heat and gives that authentic char and sizzle. Dry the meat before searing: Crucial for a proper Maillard reaction (browning). Tortillas matter: Warm them over an open flame or in a dry skillet.