In a bowl, mix the lemon juice, orange juice, Jugo Maggi, and Street Taco seasoning. Add the sliced beef, toss to coat, and let marinate while heating the griddle.
In a large bowl, combine masa harina, flour, and salt. Slowly pour in warm water while mixing by hand until the dough is soft and pliable—not sticky or dry. Cover with a damp towel and let rest for 5 minutes.
Roll the dough into golf ball–sized portions. Flatten each one into a round disk about 3 inches wide and ¼ inch thick—thick enough to slice open later.
Preheat the Blackstone griddle to medium-high. Cook the marinated beef in a single layer until browned and fully cooked. Remove and chop into bite-sized pieces.
Reduce heat to medium. Place the masa rounds on the griddle and cook 2–3 minutes per side until golden and cooked through. Wrap in a towel for a minute to keep them soft.
Using a knife, cut a slit along the side of each sope to create a small pocket (don’t cut all the way through). Fill each pocket with the chopped beef.
Top with salsa, lettuce, onion, sour cream, and cotija cheese. Serve warm and enjoy this bright, citrusy street-style twist straight from the griddle.
