Rinse and pat dry the skirt steak.
In a small bowl, whisk together the dark chili powder, 1 Tbsp lime juice, olive oil, cumin and ½ tsp garlic salt until it forms a paste.
Rub over the skirt steak then put into a storage bag to marinate for at least 2 hours or overnight.
To prepare: Oil a stovetop grill pan with a couple of drizzles of olive oil. Heat to high.
Sear the steak then lower the temperature to medium and cook for 4-5 minutes on each side.
Remove from the grill pan to a cutting board and rest for 10 minutes.
While the steak rests, peel and pit the avocados.
Mix with 3 Tbsp of sour cream, 1 ½ tsp lime juice and ¼ tsp garlic salt.
Carve the skirt steak across the grain, then build on the Ortega® Fiesta Flats™ using your favorite toppings.