Pork Tenderloin Fajitas
Pork tenderloin fajitas rely on the leanest, most tender cut of pork, sliced into even strips and seared hard and fast in a screaming-hot cast iron skillet. Because tenderloin carries almost no fat to buffer overcooking, pull it at 145°F and rest it briefly before serving — carryover heat and a short rest are what keep it from drying out. A short fridge marinade adds flavor without turning the surface mushy.
- Prep
- 20m
- Cook
- 12m
- Rest
- 3m
- Total
- 35m
- Serves
- 4
- Level
- moderate
Lean pork tenderloin, sliced thin and seared fast in cast iron, kept juicy by pulling at 145°F and resting briefly.
Ingredients
Showing ingredients for 4 servings in US customary units.
Pork
- 1½ lbPork tenderloin, trimmed of silverskin, sliced into 1/2-inch-thick medallions or 3-inch stripsSlice evenly so every piece cooks in the same amount of time.Search
- 2 tbspNeutral oilShop
- 1Lime, juicedFor the marinade only; keep the marinade time short.Search
- 2 clovesGarlic, mincedSearch
- 1½ tspChili powderShop
- 1 tspGround cuminShop
- ½ tspDried oreganoShop
- To tasteKosher saltTo taste.Shop
Peppers & onions
Cook times are not scaled with servings — adjust pan size and cook in batches as needed. Salt and “to taste” items are intentionally left for your judgment.
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Step by step
How to make it
Prep
Step 1. Trim any silverskin from the tenderloin, then slice into even 1/2-inch medallions or 3-inch strips. Even thickness matters more here than with a fattier cut — thin spots overcook first.
~8 min
Marinate
Step 2. Toss the pork with the oil, lime juice, garlic, chili powder, cumin, oregano, and salt. Cover and refrigerate 15–30 minutes — no longer, since lime acid will start to firm the surface of such a lean cut on a long soak.
~20 min
Char vegetables
Step 3. Heat a 12-inch cast iron skillet over high heat. Char the peppers and onion 6–7 minutes, tossing occasionally, until blistered and just tender. Move to a plate.
~7 min
Sear pork
Step 4. Wipe the pan and return it to high heat. Sear the pork in a single layer, working in batches if needed, 2–3 minutes per side, until well browned. Do not crowd the pan or the pork will steam instead of sear.
~5 min
Rest
Step 5. Pull the pork at 145°F on an instant-read thermometer and tent loosely with foil. Rest 3 minutes — carryover heat will finish the last few degrees.
~3 min
Combine
Step 6. If you cooked medallions, slice them thin against the grain now. Return the pork and vegetables to the pan together and toss briefly to combine and rewarm.
~1 min
Serve
Step 7. Squeeze fresh lime over the top and serve immediately with warm tortillas.
Doneness & safety
Pork (whole cuts)145°F / 63°C
Cook whole-muscle pork (tenderloin, loin) to a minimum internal temperature of 145°F (63°C), then rest 3 minutes. A faint blush of pink is safe at 145°F.
Source: USDA Food Safety and Inspection Service · reviewed 2026-07-06
Leftover storage
Refrigerate cooked fajita fillings within 2 hours (1 hour if above 90°F ambient). Store at or below 40°F, use within 3–4 days, and reheat to 165°F.
Source: USDA Food Safety and Inspection Service · reviewed 2026-07-04
Marinating safely
Always marinate in the refrigerator, never on the counter. Discard used marinade or boil it before reusing as a sauce.
Source: USDA Food Safety and Inspection Service · reviewed 2026-07-04
🛒 Shop this recipe
Pantry & spices
- neutral cooking oilShop →
- chili powderShop →
- ground cuminShop →
- oreganoShop →
- kosher saltShop →
- flour tortillasShop →
Fresh ingredients
Fresh items open an Amazon search — availability varies by location.
Cookware & tools
- Lodge 12-inch Cast Iron Skillet · L10SK3Find →
- Lodge Silicone Hot Handle Holder · ASHH11Find →
- ThermoWorks Thermapen ONE · Thermapen ONEFind →
- OXO Good Grips 12-inch Tongs · Good Grips 12" Locking TongsFind →
- Cuisinart SG-10 Electric Spice Grinder · SG-10Find →
- Glass Spice Jars with LabelsFind →
- Victorinox Fibrox Pro 8-inch Chef’s Knife · 5.2063.20 (Fibrox Pro 8")Find →
Already own these? Use what you have — no need to buy.
Recommendations are chosen to help you cook better fajitas; some Amazon links may earn a commission at no extra cost to you.
Fix it
Why pork tenderloin fajitas turn out dry
The most common cause is cooking past 145°F without accounting for carryover, since there is no fat left to carry it through the extra heat. A second cause is an overlong acidic marinade, which firms the exterior before it ever hits the pan. A third is slicing with the grain instead of against it, which leaves long muscle fibers that read as chewy even when the temperature is right.
Substitutions
| Instead of | Use | Adjust | Expect | Avoid when |
|---|---|---|---|---|
| Pork tenderloin | Boneless pork chops or pork loin | Same weight, cut into strips of similar thickness. These cuts are slightly less tender; do not extend cook time beyond 145°F. | A bit firmer bite, still lean. | — |
| Chili powder, cumin, and oregano | Store-bought fajita seasoning | About 2 tablespoons in place of the dry spices. | Comparable flavor with less control over salt. | — |
| Bell peppers | Poblano peppers | — | Deeper, slightly smoky flavor with a mild, occasional heat. | — |
The science
Why lean tenderloin overcooks so fast
Tenderloin has almost no intramuscular fat or connective tissue to buffer it, so once it crosses well past 145°F it dries out quickly with no fat to keep it moist. Carryover cooking will still push the internal temperature up another 5–10°F after you pull it from the pan, which is why timing the pull, not just watching the color, is what keeps this cut juicy.
The call: Pull the pork at 145°F and rest it briefly rather than cooking to color.
Technique
Cut evenly, then sear in batches
Because tenderloin is narrow, slicing it into uniform medallions or strips is what makes an even sear possible — uneven pieces finish at different times and you end up pulling some overdone to save others. Searing in batches, rather than crowding the whole pound into the pan at once, keeps the cast iron hot enough to brown the surface instead of steaming it, which matters more for a quick-cooking lean cut than it does for a fattier one.
The call: Slice pieces to a consistent thickness and sear without crowding the pan.
Equipment for this recipe
Disclosure: As an Amazon Associate, FajitaRecipe.com earns from qualifying purchases. Recommendations are chosen to help you cook better fajitas; some Amazon links may earn a commission at no extra cost to you. See our selection methodology.
For cast-iron fajitas
LodgeModel L10SK3
A heavy 12-inch Lodge gives two servings of steak enough hot surface to brown without crowding. It is still too small for a six-person batch, which should be seared in rounds.
Best for: Everyday 2–4 serving skillet fajitas with a hard sear.
LodgeModel ASHH11
A cast-iron handle reaches the same temperature as the pan. A slip-on holder is the difference between confidently moving the skillet and dropping it.
Best for: Anyone using a blazing-hot cast-iron or carbon-steel handle.
ThermoWorksModel Thermapen ONE
Thin fajita chicken and steak swing past target in seconds. A one-second read lets you pull chicken at 165°F and steak at your chosen doneness before carryover overshoots.
Best for: A one-second, dependable read on thin proteins.
OXOModel Good Grips 12" Locking Tongs
Twelve-inch tongs keep your hand out of the smoke while you toss peppers and flip strips in a ripping-hot pan.
Best for: Tossing peppers and turning strips over high heat.
For making seasoning
CuisinartModel SG-10
Toasting whole cumin and grinding it fresh gives a homemade seasoning noticeably more aroma than pre-ground jars that have sat for months.
Best for: Grinding whole cumin and dried chiles for a fresher blend.
Homemade blend keeps its potency about six months in an airtight jar away from light and stove heat — worth it if you mix a big batch.
Best for: Storing homemade fajita seasoning so it keeps its punch.
For peppers & onions
VictorinoxModel 5.2063.20 (Fibrox Pro 8")
A sharp 8-inch chef’s knife handles the pepper and onion prep fajitas live on. The Fibrox handle grips even when your hands are wet from vegetables.
Best for: Slicing peppers and onions and general prep.
OXOModel Good Grips 12" Locking Tongs
Twelve-inch tongs keep your hand out of the smoke while you toss peppers and flip strips in a ripping-hot pan.
Best for: Tossing peppers and turning strips over high heat.
Serving & storage
Storing and reheating
Refrigerate leftovers within two hours and use within 3–4 days. Reheat gently in a covered skillet over medium-low heat or in a low oven — lean pork has little fat to fall back on, so a hard, fast reheat will dry it out just as easily as overcooking it the first time.
Frequently asked questions
+What temperature should pork tenderloin fajitas be cooked to?
Pull the pork at 145°F on an instant-read thermometer, then rest it 3 minutes. Carryover heat will carry it the rest of the way safely without drying it out.
+Can I marinate pork tenderloin overnight?
Keep an acidic, lime-based marinade to 30 minutes or less in the fridge. For a longer marinade, leave the lime juice out and add it as a finishing squeeze instead, so the acid never has time to firm the surface.
+Why is my pork tenderloin fajita meat dry?
Almost always overcooking past 145°F without accounting for carryover heat, since tenderloin has no fat to fall back on. Slicing with the grain instead of against it can also make properly cooked pork read as tough.
+Can I use a different cut of pork?
Yes — boneless chops or pork loin work well sliced into strips of similar thickness. They are slightly less tender than tenderloin but still lean, so watch the same 145°F target.
Testing, sources & disclosure
This recipe was developed and reviewed by our editors. We publish full kitchen-test notes here once a recipe has been cooked and verified in our kitchen.
- Author:
- FajitaRecipe Editorial
- Last reviewed:
- 2026-07-06
Sources
- Safe Minimum Internal Temperature Chart, USDA FSIS linkSupports: Pork should reach a safe minimum internal temperature of 145°F with a rest time
As an Amazon Associate, FajitaRecipe.com earns from qualifying purchases. We do not provide medical or dietary advice; follow USDA guidance for food safety.
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