Created by breezermom on March 15, 2020
Step 1: Place the flank steak in a large zip-top plastic freezer bag.
Step 2: Stir together the lime juice, cilantro, garlic powder, 1 tablespoon cumin, 1 tablespoon ancho chili powder, and 2 teaspoons kosher salt. Whisk in 1/4 cup olive oil. Pour over the steak in the bag. Seal the bag and turn to coat. Marinate in the refrigerator for 1 to 12 hours.
Step 3: Place the oven rack about 6 inches from the top of the oven. Preheat the oven to 450 degrees F.
Step 4: Rinse the tomatillos and cut them into quarters. Stir together the tomatills, sweet potatoes, red onion, and remaining 1 teaspoon cumin, 1 teaspoon ancho chili powder, 2 teaspoons salt, and 2 tablespoons oil in a large bowl. Spread the sweet potato mixture in an even layer on an aluminum foil lined sheet pan.
Step 5: Bake at 450 degrees F for 20 minutes. Remove from the oven, and move the sweet potato mixture to the sides of the sheet pan. Place the flank steak in the center of the sheet pan. Increase the oven temperature to broil.
Step 6: Broil for 6 minutes. Turn the steak over and broil 6 minutes more. (Stir the vegetable mixture if they begin to char or remove them from the pan). Remove from the oven and let stand for 5 minutes.
Step 7: Cut the steak across the grain and drizzle with the pan drippings.
Step 8: Place some sour cream in a small bowl. Stir in a bit of the pan drippings. Mix well.
Step 9: Serve the steak with the potato mixture, with tortillas, sour cream, and fresh cilantro.