Step 1

Whisk all marinade ingredients together. Reserve 2 tablespoons of marinade in a separate bowl. Pour remaining marinade over skirt steak in a resealable bag and refrigerate for 4 to 24 hours. Massage the meat periodically to redistribute marinade.

Step 2

Heat 2 tablespoons of olive oil in a large skillet over medium-high heat. Add onions and saute for 4-5 minutes until slightly softened. Add bell peppers and cook another 3 minutes, stirring frequently, until slightly softened.

Step 3

Reduce heat to medium and continue to cook for 5 to 8 minutes, stirring often, until the peppers and onions are slightly seared, softened, and starting to caramelize. Add reserved marinade and scrape the bottom of the pan with a wooden spoon to deglaze the pan.

Step 4

To cook the meat, heat a grill to medium-high heat or heat a cast iron skillet over medium-high heat with 1 tablespoon of olive oil. Remove the meat from the marinade and discard the marinade. Cook the meat for 3 to 4 minutes per side until medium-rare. You may need to cut the steak in half and cook it in batches if your skillet isn't big enough. Remove the meat from the grill or pan to a cutting board and let it rest for 5 to 10 minutes before slicing against the grain into 1/2-inch strips.

Step 5

Add the cooked, sliced steak to the fajita veggies and toss to combine. Sprinkle with additional cilantro, if desired. Serve with warmed flour tortillas, pico de gallo, sour cream, cheese, and guacamole for individual assembly.