Heat a pan over medium-high heat. Add 1 tablespoon of avocado oil. Add onions and serrano peppers. Cook until onions begin to soften, about three minutes.
Add shredded beef, cumin, chili powder, garlic granules, Mexican oregano, salt, and black pepper. Stir spices into the beef mixture and cook for about 45 seconds. Add your drained tomatoes and stir into the mixture.
Add lime juice and stir.
Turn off the heat. Add cheese and stir into the mixture. Set aside to cool while you heat up your tortillas.
Heat up tortillas until warm and pliable.
Fill tortillas with 2 to 3 tablespoons of beef mixture and roll into a cigar shape.
Heat a frying pan over medium-high heat. Add 2 tablespoons of avocado oil. Once heated(about 2 minutes) add the flautas, you may need to do this in batches. Turn heat down to medium and fry the flautas until golden brown on each side.
Garnishes: shredded lettuce, tomatoes, green onions, olives, cheese, jalapeños, tomatoes, plain yogurt, sour cream, or anything else that sounds good to you.