Method
To make the marinade for the skirt steaks, combine 1/2 cup of the cilantro, 1/2 cup of the lime juice, 1/4 cup of the parsley, and 2 cups of the Wish-Bone Dressing. Hold refrigerated.
To make the sauce, combine the remaining 1/2 cup cilantro, 1/4 cup lime juice, 1/2 cup parsley, 1 cup Wish-Bone Italian Dressing, and the garlic. Hold refrigerated.
Marinate the skirt steaks in the reserved marinade for 2 hours. Drain, grill until medium rare, and slice thinly.
To assemble each sandwich, mound 4 oz of the steak onto 1 slice of the sourdough. Top with 3 slices of tomato, 2 slices red onion, 2 Tbsp of the sauce, and the remaining slice of bread.