Slow-Cooker Pineapple Al Pastor Pork & Red Pepper Fajitas

Forget the grill—this al pastor gets its smoky-sweet magic from a slow cooker. Pork loin strips simmer for six hours in a bright achiote-guajillo pineapple sauce, surrounded by sweet pineapple chunks and red bell peppers.

The result is meltingly tender meat with a subtle char-like depth, finished with a blanket of melted Chihuahua cheese. Pile it into charred corn tortillas and top with avocado, crema, and a squeeze of key lime for the easiest Taco Tuesday ever.

This slow-cooker al pastor fajita recipe brings the vibrant flavors of Mexican street tacos to your countertop with almost no effort. The pork loin strips cook low and slow in a bold sauce made from achiote, guajillo chiles, and pineapple, which tenderizes the meat and infuses it with a sweet-smoky character.

Red bell peppers and red onion soften into the sauce, while fresh pineapple chunks caramelize and melt into the surrounding liquid. After six hours, the pork is fork-tender and ready to be piled into warm corn tortillas with all your favorite toppings.

Ingredients

Why this recipe works

The slow cooker does the work of a traditional al pastor trompo: it gently breaks down the pork loin over hours, so the meat turns tender and juicy without drying out.

The pineapple adds natural sweetness and a touch of acidity, which helps balance the earthy heat of the guajillo chiles. Cooking on LOW for a full six hours lets the flavors meld and deepen, just like a long marinade—but without any active time.

This method is also forgiving. Because the pork is surrounded by moisture from the pineapple and sauce, it stays succulent even if the cook time runs a little long. The addition of Chihuahua cheese at the end brings a creamy, salty finish that ties the whole dish together. The result is a fajita filling that tastes like it came from a taqueria, but requires only a few minutes of prep.

Notes and substitutions

Pork loin is a lean, mild cut that works perfectly here because it's cooked in a moist environment. If you prefer a richer result, pork shoulder (butt) is a great substitute—just increase the cook time to 8 hours on LOW and shred the meat instead of slicing it.

The achiote-guajillo pineapple sauce is the flavor backbone; look for a store-bought version or make a quick homemade blend of achiote paste, guajillo chiles, pineapple juice, garlic, and spices.

Chihuahua cheese is a Mexican melting cheese with a mild, buttery flavor. If you can't find it, Monterey Jack or mild cheddar are excellent stand-ins. For the tortillas, corn tortillas are classic, but flour tortillas also work. The charring step is optional but recommended—it adds a subtle smoky note that echoes the al pastor's traditional preparation.

• pork loin: pork shoulder (butt) works too; cook 6-8 hours on low until shreddable, then shred or slice.
• Chihuahua cheese: Use Monterey Jack or mild cheddar if Chihuahua cheese is unavailable.
• fresh pineapple: Canned pineapple chunks (drained) are fine; reduce salt slightly since the brine adds salt.
• achiote-guajillo sauce: Use store-bought achiote paste blended with pineapple juice and guajillo chiles, or a mild enchilada sauce.

Equipment

• Slow cooker (6-quart)
• Cutting board
• Chef's knife
• Measuring cups
• Mixing spoon
• Tongs
• Skillet for charring tortillas (optional)