1-First Step: Prepare Marinade and Ingredients Peel and juice 1 to 2 large oranges and 2 medium limes to yield approximately 3/4 cup combined citrus juice. Finely grate or mince 4 garlic cloves. Chop cilantro stems for marinade, reserve leaves for garnish. Slice the red onion thinly for grilling.

2-Second Step: Marinate the Steak and Onions In a dish or resealable bag, combine orange juice, lime juice, garlic, chopped cilantro stems, 1/2 cup chipotle salsa or 1-3 teaspoons chipotle in adobo, sliced red onions, 2 teaspoons kosher salt, 1 teaspoon black pepper, and 2 tablespoons oil. Add flank steak and coat thoroughly. Refrigerate for 1 to 4 hours, flipping halfway to ensure even marination. Avoid over-marinating to prevent meat from becoming mushy due to acidity.

3-Third Step: Preheat Grill and Prepare for Cooking Heat a grill pan, outdoor grill, or skillet to medium-high heat (about 400ºF/204ºC). Remove steak and onions from marinade, discard marinade, and gently brush off excess pieces to prevent burning.

4-Fourth Step: Cook Grilled Steak and Onions Season steak on both sides with salt and pepper. Cook onion slices for about 5 minutes until charred and tender, then push aside on the grill. Sear steak 4 minutes per side for medium-rare (internal temp 128ºF/53ºC) or 5 minutes per side for medium (135ºF/57ºC). Remove steak and let rest 10 minutes to retain juices.

5-Fifth Step: Warm the Tortillas Warm tortillas by charring quickly over an open flame, heating them in a skillet, or microwaving wrapped in a damp towel until soft and pliable.

6-Final Step: Assemble and Serve Slice rested steak thinly against the grain into 1/2-inch thick pieces. Spread avocado crema or sour cream on tortillas, top with sliced steak, grilled onions, salsa fresca or pico de gallo, crumbled Cotija or queso fresco cheese, and fresh cilantro leaves. Serve immediately with optional lime wedges and hot sauce for added flavor. For vegan or gluten-free adaptations, substitute steak and tortillas accordingly.