The secret to this dish is prep: Do the searing and make the sauce ahead of time, so that all you have to do when you're ready to sit down is throw it quickly in the oven. I used top sirloin for this dish, which works well. Try to buy one that is 11/2 inches to 2 inches thick. You could upgrade to New York sirloin but the cost will double. If ancho chilli powder is not available, then use regular chilli powder, but omit the cumin. The vegetables vary depending on the season, and zucchini, sweet potatoes, corn, poblano peppers are all perfect in this.
Slice meat onto each plate or serve family style, sliced on a platter surrounded by the vegetables. Serve with corn tortillas or mashed sweet potatoes.