How to Make It
Heat 1 tablespoon of the oil in a large skillet over medium-high heat. Season the steaks with 1/2 teaspoon salt and 1/4 teaspoon pepper. Cook until an instant-read thermometer inserted into the thickest steak registers 130° F, 2 to 4 minutes per side for medium-rare. Let rest for 5 minutes; thinly slice against the grain.
Meanwhile, heat the remaining tablespoon of oil in a separate large skillet over medium heat. Add the chorizo, chard stems, onion, and 1/4 teaspoon each salt and pepper. Cook, stirring occasionally, until the onion is soft, 6 to 8 minutes. Add the chard leaves and cook until wilted, 2 to 3 minutes.
Top the tortillas with the steak, chard, and sour cream. Serve with the lime wedges and hot sauce.