For the grilled beef, in a bowl, mix all the ingredients and rub the meat.
Preheat oven to 200 °C (400 °F). In a hot pan, grill the meat on both sides and finish cooking in the oven for 5 to 10 minutes according to the desired cooking. Allow to rest for 10 minutes before slicing.
For the vegetables, in the same pan, cook the vegetables until golden brown. Season with cumin, salt and pepper and set aside.
For the avocado salsa verde, mix all the ingredients and season with salt and pepper.
Spread the sour cream on the tortillas and garnish with sliced meat, grilled vegetables and avocado salsa verde.