Place the full cut of meat into the freezer for 10 to 15 minutes, as it will be easier to slice. After freezing, slice the steak into ½-inch strips against the grain. Season the meat with ½ tablespoon of the fajita seasoning.
Turn the Instant Pot to Saute and add in 1 teaspoon of oil and let heat.
Once the oil is heated, add half the seasoned meat to the Instant Pot in a single layer. Saute for about 1-2 minutes per side, to JUST brown the steak. Remove the seared meat from the inner pot and place it on a plate. Repeat the process with the remaining meat, adding in an additional teaspoon of oil if needed. Once browned, remove the steak to the plate with the first batch, and drain off any grease if needed.
Turn the Instant Pot off by hitting cancel, Add in ½ cup beef broth for a 3 or 6-quart Instant Pot or ¾ cup for an 8-quart model. Use a wooden or metal spatula to scrape up any browned bits off the bottom of the inner pot.
Add the seared beef back to the inner pot. Top the meat with the sliced onion and sliced peppers. Sprinkle the additional ½ tablespoon of fajita seasoning over the pepper and onions.
Seal instant pot, being sure vent knob is pointed to sealed. Set to cook on High Pressure for 2 minutes. Once cooking time is finished let pressure release naturally for10 minutes, to keep the meat tender.
Remove the meat, onions, and peppers to a serving platter using a slotted spoon. Add the zest and juice of the limes and toss to coat.
Serve the fajita mixture as desired on tortillas or over rice with your favorite toppings.
Fajita Seasoning: I use my homemade blend of fajita seasoning which is made with smoked paprika, garlic powder, onion powder, and cumin. You can use store-bought seasoning or even taco seasoning to flavor these fajitas.Doubling the Recipe: To double, double the meat, peppers, onions, and seasonings, but keep the amount of liquid the same. The cooking time will also remain the same. Storage: Store leftover steak fajita mixture in an airtight container in the refrigerator for up to 3 days. Leftover Cooking Liquid: The extra cooking liquid makes a great flavoring when preparing rice in the Instant Pot.