|1⁄2||cup chopped fresh cilantro|
|1⁄2||cup each canola oil and fresh lime juice|
|4||Tbsp. chipotle sauce|
|2||Tbsp. minced fresh garlic|
|2||Tbsp. distilled white vinegar|
|11⁄2||tsp. kosher salt|
|1||tsp. each ground cumin and black pepper|
|1||top sirloin, trimmed (1½ lb.)|
|2||Tbsp. canola oil|
|2||red bell peppers, sliced|
|1||sweet onion, sliced|
|6||burrito-size flour tortillas (10-inch)|
|2||cups chopped romaine lettuce|
|2||avocados, peeled, pitted, and sliced|
|6||Tbsp. purchased pico de gaillo|
|2||Tbsp. chopped fresh cilantro|
Combine ½ cup cilantro, ½ cup oil, lime juice, chipotle sauce, garlic, vinegar, salt, cumin, and black pepper in a large bowl.
Add steak to marinade; toss to coat. Cover bowl with plastic wrap; chill 4–12 hours, flipping steak occasionally.
Heat 2 Tbsp. oil in a large cast-iron skillet over high until it shimmers. Remove steak (reserving ¼ cup marinade) and season with salt and black pepper; cook 5–7 minutes per side for medium-rare. Transfer steak to a cutting board; tent with foil and let rest 10 minutes. Slice steak against the grain.
Sauté bell peppers and onion in drippings in skillet with reserved marinade over medium-high heat until crisp-tender, 3–5 minutes.
Warm tortillas in a large nonstick skillet over low heat.
Divide steak, bell pepper-onion mixture, romaine, avocado, pico de callo, and 2 Tbsp. cilantro among tortillas. Fold sides of tortilla into center, then roll edge closest to you over the filling; continue rolling and tucking in filling until enclosed.