Marinate the steak:
Lay the skirt steak flat on a cutting board and cut the steak 2 to 3 equal pieces so that you do not have one long piece and place in a baking dish or large bowl. Make the marinade by whisking the olive oil, garlic, lemon juice, and salt together. Pour the marinade over the skirt steak and let the meat marinate for 15-20 minutes.
Grill the corn:
Rub the ears of corn with the olive oil and grill on medium heat for 12 minutes, rotating the ears as they cook to get an even char. Remove the corn from the grill and cut the corn off of each cob by holding the flat end of the ear upright in the bottom of a wide, big bowl and carefully slicing down the side of the ear to release the kernels. Set the corn aside.
Grill the steak:
Set your grill to medium-high heat. Grill the steak until medium-rare, about 3 minutes on one side then flip and grill for 1 to 2 more minutes, depending on the thickness of your meat. Let rest for a few minutes. Cut the steak into cubes by slicing the steak against the grain first then cutting the slices into ½-inch cubes. Set aside.
Make the dressing:
Blend all the dressing ingredients to combine well. Taste the dressing and add salt, pepper, and more lemon juice for extra tang, if needed. If you want the dressing thicker, feel free to add more herbs. Store in a jar in the refrigerator until you’re ready to use it.
Make the salad:
In a large bowl add your romaine and sprinkle a large pinch of salt. Add the steak, corn, and avocado. Sprinkle the cotija cheese on top and drizzle a few tablespoons of the dressing. Add some marinated red onions and sprinkle the chives then squeeze a few lemon wedges over top. Toss the salad until well combined then serve and enjoy!