In a medium bowl, combine the cilantro, garlic, shallot, serrano pepper, toasted cumin seeds, lime juice, 1/4 cup of the olive oil and tequila. Whisk to combine and place in a 1-gallon re-sealable food storage bag with the flank steak. Allow to marinate at room temperature for 45 minutes.
Preheat a grill or grill pan to medium-high heat and brush the grates with an oil soaked rag. Remove the steak from the marinade and scrape off any excess marinade. Season the steak on both sides with 1 1/2 teaspoons of the kosher salt and the black pepper. Place on the grill and cook for 2 minutes, rotate 45 degrees and cook another 2 minutes. Turn over and cook for another 2 minutes, rotate 45 degrees and cook for a final 2 minutes. Remove from the grill and allow to rest for 5 minutes on a cutting board before slicing against the grain.
Set a 12-inch saute pan over medium-high heat and add the remaining 2 tablespoons olive oil. Once the oil is hot, add the green, red and yellow bell peppers as well as the remaining 1/4 teaspoon of the kosher salt to the pan and saute, stirring often until the peppers are softened and well caramelized, about 4 to 5 minutes.
Toast the tortillas in a hot dry pan, or directly over an open flame until lightly toasted and warmed through. Serve the tortillas with the steak, peppers, Guacamole and Chipotle Mayonnaise.
4 Hass avocados, peeled and mashed
2 limes, juiced
1/4 cup finely chopped red onion
2 jalapeno peppers, seeded and minced
3 cloves garlic, minced
3/4 teaspoon salt, or to taste
Combine all ingredients in a small bowl and stir until thoroughly combined. Cover tightly with plastic wrap and set aside, refrigerated, until needed. Should be made as close to serving time as possible.
Yield: about 1 1/2 cups
1 cup mayonnaise
2 cloves garlic, minced or pressed
1 chipotle pepper in adobo sauce
1 teaspoon lemon or lime juice
1/2 teaspoon ground cumin
1/2 teaspoon Mexican oregano
Combine all ingredients in the bowl of a food processor and process until smooth, about 1 to 2 minutes. Transfer to a small bowl and refrigerate until needed.
Yield: about 1 cup