Pour oil in saute pan on medium flame. Add the onions and bell pepper and cook until soft. Add shrimp, garlic, serranos, and Mexican seasoning. Cook for 7 minutes, or until shrimp are cooked. De glaze the pan with tequila and let simmer for 1 minute.
Place veggie mix in the tortilla, then add shrimp, lettuce, cheese, and pico de gallo. Top with sour cream.