In a gallon size resealable bag combine lime juice, orange juice, lemon pepper, smoked paprika, garlic, tequila, cumin, and salt.
Add the flank steak to the bag with the marinade, press out the excess air from the bag, and seal tightly.
Massage in the marinade around the meat, place the bag on a bowl and refrigerate overnight. Turn bag to the other side, half way through the marinade process (allow both sides to marinade).
Take out the flank steak out of the refrigerator.
Preheat the grill to medium-high heat, then place the flank steak on the grill. Cook for about 4 minutes and turn the steak, and cook for another 4 minutes (create grill marks). Flip over the flank steak and continue cooking until desired doneness (Rare: 120-130 °F, Medium-rare: 130-140 °F, Medium: 140-150 °F, Well-done: 150-165 °F).
Transfer flank steak to a cutting board and cover with aluminum foil. Let the steak rest for 10 minutes.
Slice against the grain into strips. And Voila! Enjoy!