2 jalapeños, stem and seeds removed, sliced into strips
2 avocados, sliced
1 beefsteak tomato, chopped
¼ c (10 g) cilantro, chopped
Combine all the marinade ingredients in a gallon-sized (3-3/4 L) zip top plastic bag. Place the skirt steak in the bag, press out the excess air and seal. Lightly massage the bag to make sure the marinade coats every inch of the skirt steak. Place in the fridge to marinate for 1 hour.
Heat a cast-iron pan over medium-high heat. Remove the skirt steak from the bag and set aside the remaining liquid. Generously season both sides of the skirt steak with sea salt and black pepper. Place the steak on the pan and sear for 5 minutes. Flip to the other side for another 5 minutes for medium. Remove from the pan. Place it on a cutting board and cover with foil to rest.
While the skirt steak is resting, scrape off any excess burned brown bits that are stuck to the bottom of the pan. Add the sliced bell peppers, onion and jalapenos. Add the marinade that was used for the meat and sauté vegetables for 4 to 5 minutes. Turn off the heat. Thinly slice the skirt steak across the grain and place on a large serving plate. Top with the cooked fajita vegetables, avocado slices, chopped tomato, and cilantro.