Grilled Steak Fajitas are an easy summer dinner made with marinated flank steak, bell peppers and onions, ready in 20 minutes on the grill. Because the pineapple soy marinade does its work in under two hours, this quick recipe suits weeknight dinners, backyard cookouts or a party crowd.
The marinade time is the step that decides everything, since pineapple juice contains bromelain, an enzyme that breaks down protein. Thirty minutes to two hours gives tender, evenly seasoned beef, but anything longer turns the steak soft and mealy inside.
This version pairs sweet pineapple juice with salty soy sauce, which brines the meat and adds a savory depth most fajita marinades miss. Half a cup of that marinade gets reserved and poured over the steak and vegetables after grilling, so the flavor lands twice.
Grilled Steak Fajitas
Course: DinnerCuisine: American, Tex-MexDifficulty: Easy24
servings1
hour20
minutes198
kcalFlank steak soaks in pineapple juice, soy sauce and lime, then grills over medium heat alongside peppers and onions. Everything gets sliced thin against the grain and wrapped in toasted flour tortillas with whatever toppings you like.
Ingredients
- For the Marinade:
¾ cup pineapple juice
¾ cup soy sauce
1 tablespoon Worcestershire sauce
Zest and juice of 1 lime
1 clove garlic, minced (or 1 teaspoon garlic powder)
- For the Fajitas:
1 flank steak (about 1.5 pounds, 1 inch thick), or skirt steak or flat iron steak
3 green bell peppers (or a mix of red, green and yellow)
1 large onion
3 serrano or jalapeno peppers
1 teaspoon kosher salt or fine sea salt
20 to 24 fajita size flour tortillas
- Accompaniments (optional):
Shredded lettuce
Shredded cheese
Sour cream
Salsa
Lime wedges
Directions
- Marinate the beef:Mix the pineapple juice, soy sauce, Worcestershire sauce, lime zest and juice, and minced garlic. Set ½ cup aside for later. Pour the rest into a gallon zip-top bag, add the flank steak, press out the air and marinate 30 minutes to 2 hours. Do not go past 2 hours or the pineapple will make the meat too soft.
- Prep the vegetables:Core and seed the bell peppers, then cut each into 3 to 4 large flat planks. Cut the onion into ½-inch thick slices. Sprinkle the peppers and onions with 1 teaspoon salt. Leave the serrano or jalapeno peppers whole.
- Preheat the grill:Set the grill up for direct medium heat, about 350°F. On a gas grill, preheat all burners on high for 10 to 15 minutes, brush the grates clean, then turn down to medium. For charcoal, light a chimney ¾ full, wait until the coals are ashed over, then spread them in a tight single layer over half the grate.
- Grill the steak and vegetables:Let excess marinade drip off the steak. Put the steak, pepper planks, onions and hot peppers over direct heat. Grill in a 3-3-3-3 pattern: 3 minutes, flip, 3 minutes, flip and rotate 90 degrees for crosshatch marks, 3 minutes, flip, 3 more minutes. The steak is done at 125°F for medium. Move the steak to a baking dish and the vegetables to a bowl, then pour ¼ cup reserved marinade over each and toss to coat.
- Toast the tortillas:Brush the grates clean. Lay as many tortillas as fit in a single layer and toast 30 seconds to 1 minute per side, until light grill marks appear and the tortillas start to puff. Wrap them in a cloth towel and repeat in batches.
- Slice and serve: Pull the hot peppers from the bowl, peel off any blackened skin, slice thin and put them in a small dish. Slice the bell peppers into ½-inch strips and halve each onion ring, then toss again in the marinade. Cut the steak in half lengthwise, slice each piece crosswise as thin as possible, and pour any board juices over the top. Serve with the tortillas.
FAQs
Can you cook these fajitas indoors without a grill?
A cast iron skillet or grill pan over medium high heat works, though you will cook the steak and vegetables in separate batches. The broiler is another option, since it puts the steak about four inches from direct heat and browns it fast. Neither method gives you grill marks, but the pineapple soy marinade carries most of the flavor anyway.
Why set aside half a cup of the marinade before adding the steak?
Marinade that has touched raw beef is not safe to pour over cooked food, so a clean portion gets reserved at the start. That reserved half cup goes over the rested steak and vegetables, which returns the seasoning that cooking burns off. Boiling the used marinade for a full minute would work too, though reserving is simpler.
Why grill the bell peppers in large planks instead of strips?
Large flat planks sit securely on the grates, so nothing slips through into the fire the way thin strips would. The wide surface also takes on char faster than a narrow piece, which builds smoky flavor before the pepper goes limp. Slicing after grilling gives you clean strips with all that color and char intact.
Why cut the flank steak in half lengthwise before slicing it?
Flank steak is long, so halving it lengthwise gives you two shorter pieces that are much easier to slice thin. It also shows the direction of the muscle fibers clearly, which makes cutting across the grain far simpler. Slicing with the grain leaves long fibers intact and the beef chewy, so this small step matters.
How should you store leftover fajita steak and vegetables?
Keep the sliced steak and vegetables in separate airtight containers in the fridge for up to three days. Reheat the beef quickly in a hot skillet, since slow reheating overcooks the thin slices and dries them out. Tortillas store best at room temperature, so wrap them in foil and keep them out of the fridge.
