Place skirt steak in a large ziploc bag.

In a small bowl, whisk together orange juice, chili powder, oregano, and cumin.

Set aside the marinade.

Place half of the sliced onions and citrus fruits on each side of the skirt steak in the ziploc bag.

Pour the orange juice mixture over the steak, onions, and citrus.

Close the bag securely and place in a container to prevent leaks.

Refrigerate for 2 to 4 hours, or preferably overnight, to marinate.

To make the chili mayonnaise, whisk together mayonnaise, chili powder, and cumin in a small bowl.

Cover and refrigerate until ready to use.

Preheat an outdoor grill to medium-high heat.

Slice the torta rolls in half lengthwise.

Spray each side of the rolls with vegetable cooking spray.

Place the rolls, cut side down, on the heated grill.

Cook for 1-2 minutes, watching carefully to avoid burning.

Remove the rolls from the grill and keep them warm.

Remove the meat from the marinade and grill for 4-5 minutes per side, or until the desired degree of doneness is reached.

Remove the grilled steak from the grill and place it on a rimmed cutting board.

Slice the steak across the grain into 1/2-inch strips.

Spread each half of the torta roll with an equal portion of chili mayonnaise.

Layer a portion of the sliced carne asada on the bottom half of each roll.

Top with desired garnishes such as fresh salsa, sliced avocado, and shredded lettuce.

Serve immediately and enjoy!