Steak and Shrimp Fajita Skillet with Sizzling Lime Butter Step-by-step instructions

Before you start

Take the steak out of the refrigerator 30 minutes before cooking so it sears evenly from edge to edge; the shrimp can stay chilled until the moment they hit the pan. Slice the peppers and onion into strips of even thickness so they char at the same rate. Mince the garlic, juice the limes, and measure the rub into one bowl so the marinade comes together in a minute.

Instructions

Marinate in lime, soy, and garlic

1. 1Whisk the lime-soy marinade
   In a medium bowl, whisk 3 tbsp of the lime juice with the soy sauce, 1 tbsp of the avocado oil, the minced garlic, and the chili-cumin rub. Whisk until the rub dissolves and the marinade looks uniform and slightly glossy, with no clumps of spice clinging to the bottom of the bowl.
   Look for The Marinade should smell sharply of lime and garlic with a dark, even color.
   Tip Zest the limes before juicing and add a little zest to the marinade for extra citrus aroma.
2. 2Marinate the steak and shrimp
   Put the skirt steak in a shallow dish and the shrimp in a separate small bowl. Pour most of the marinade over the steak and turn to coat; cover and refrigerate for at least 30 minutes and up to 2 hours. Spoon the rest over the shrimp and refrigerate for no more than 15 minutes, since the lime will firm the shrimp quickly.
   Look for The steak should be evenly coated and the shrimp just turning opaque at the edges.
   Tip Keep both proteins on the bottom shelf of the refrigerator while they marinate.

By the end of this phase the steak has sat at least 30 minutes in the refrigerator, coated in the lime-soy marinade, and the shrimp have had a short 15-minute soak of their own. The steak surface should look slightly darkened and tacky from the soy; the shrimp should be just turning opaque at the edges, never fully firm.

Before moving on, pull both from the fridge, lift the steak from its marinade and let it drip, and pat the shrimp dry with paper towels — dry surfaces are what brown on hot iron.

Sear on a 500°F skillet

3. 3Heat the cast-iron skillet hard
   Place a 12-inch cast-iron skillet over high heat and let it sit empty for 5 to 8 minutes, until a drop of water skitters and evaporates on contact. You are aiming for roughly 500°F (260°C) at the cooking surface. Add the remaining 1 tbsp avocado oil and swirl to coat just before the vegetables go in.
   Look for The oil should shimmer and thin out instantly, with the first wisp of smoke rising.
   Tip Run the kitchen vent or open a window; a properly hot skillet will smoke briefly.
4. 4Sear the peppers and onions
   Add the bell peppers and onion to the hot skillet in a single layer. Sear for 3 minutes, tossing only once or twice with tongs, until the edges blacken in spots and the vegetables stay crisp-tender. Slide them onto a plate and set aside, leaving the skillet on the heat.
   Look for Look for blistered, dark-edged strips that still hold a slight bite in the center.
   Tip Resist stirring constantly; contact with the hot iron is what builds the char.
5. 5Sear the skirt steak
   Lift the steak from its marinade, letting the excess drip off. Lay it in the dry-hot skillet and sear 3 to 4 minutes per side for medium-rare, until an instant-read thermometer reads 145°F (63°C) at the thickest point. Transfer to a cutting board and let the steak rest at least 3 minutes before slicing against the grain into thin strips.
   Look for A deep brown crust should form on both sides with a rosy interior when sliced.
   Safe temperature 145°F (63°C) internal temperature (steaks, chops and roasts)
   Tip Skirt steak is thin, so watch the clock closely past the 3-minute mark per side.
6. 6Sear the shrimp
   Add the shrimp to the same skillet in one layer and sear about 1 to 2 minutes per side, flipping once, until they curl into a loose C and reach 145°F (63°C) at the thickest part. They should be opaque all the way through with golden edges. Transfer immediately to a clean plate so they do not keep cooking.
   Look for Shrimp are done when plump, opaque, and just curled — not tightly coiled.
   Safe temperature 145°F (63°C) internal temperature (shellfish)
   Tip Pat the shrimp dry before searing so they brown instead of steaming.

This is the loud phase. The peppers and onions should come out blistered, dark-edged, and crisp-tender. The steak should show a deep mahogany crust on both sides, register 145°F (63°C), and have rested at least 3 minutes before it is sliced against the grain into thin strips.

The shrimp should be opaque, plump, and curled loosely, pulled from the pan the instant they reach 145°F (63°C). Check before moving on: the skillet will be coated with browned bits, which is exactly what the lime butter needs.

Lime butter and tableside pour

7. 7Make the sizzling lime butter
   Lower the heat to medium and add the butter to the skillet with the remaining 1 tbsp lime juice. Swirl as it melts and foams, scraping up the browned bits, for about 1 minute. The butter should smell toasty and citrusy and turn lightly golden. Keep it in the pan or pour it into a small hot pitcher for tableside service.
   Look for The butter foams and the skillet gives a loud, steady sizzle when the lime juice hits.
   Tip Have the butter cold from the fridge so it foams rather than browning too fast.
8. 8Char the tortillas
   While the butter finishes, warm the tortillas directly over a gas flame or in a dry skillet for about 20 seconds per side, until they puff slightly and show toasted brown spots. Stack them under a clean kitchen towel to stay soft and steaming until assembly.
   Look for The tortillas should be flexible with light char marks, never crisp or cracked.
   Tip No gas flame? A dry cast-iron pan over medium-high heat does the same job.
9. 9Build and pour tableside
   Pile the peppers and onions back into the skillet, then top with the sliced steak and shrimp. Bring the whole skillet to the table on a trivet, spoon guacamole and cheddar alongside, and pour the sizzling lime butter over everything in front of your guests. Wrap the filling in warm tortillas and finish with a squeeze of charred lime.
   Look for The pour should set off a burst of steam and sizzle the moment it hits the skillet.
   Tip Warm the serving plates too so the filling stays hot through the whole meal.

The finish is fast and dramatic. The butter should have melted, foamed, and picked up every browned bit from the skillet, turning lightly golden and smelling of toasted citrus.

Tortillas are charred in spots, flexible, and stacked under a towel to stay steaming. When the peppers, onions, sliced steak, and shrimp are piled back into the skillet and the butter is poured over at the table, the pan should hiss and throw a plume of steam.

Common mistakes

The most common error is a lukewarm skillet: if the oil does not shimmer and smoke slightly, the vegetables weep liquid and the steak steams instead of browning. Give the empty pan a full 5 to 8 minutes over high heat. The second trap is marinating the shrimp too long; more than 15 to 20 minutes in lime juice and the texture turns dense and chalky. Third, overcooking the shrimp past a tight curl.

How to tell it’s done

The steak is done at 145°F (63°C) internal temperature for medium-rare with a safe margin, followed by a 3-minute rest; the interior should be rosy pink with a dark brown crust outside.

Shrimp are done at 145°F (63°C) at the thickest part: opaque throughout, plump, and curled into a loose C shape — a tight O means they are overcooked. Peppers and onions should be blistered in spots but still hold a slight snap.

• Steaks, chops and roasts: 145°F (63°C) in the thickest part, then a 3-minute rest
• Shellfish: 145°F (63°C) in the thickest part