For the chimichurri steak

1. Make marinade. Place the parsley, garlic, olive oil and vinegar in a food processor and pulse until well chopped, but not puréed, scraping down the sides of the bowl as necessary. Set aside.
2. Season steak. Generously season both sides of the steak with salt and pepper. Then rub each side with about 1 tablespoon of chimichurri sauce.
3. Cook steak. Heat the oil in a large, heavy duty cast iron skillet over high heat until almost smoking. Add the steak and cook, turning once, 4 to 5 minutes per side for medium-rare, or until done to your liking.
4. Rest steak. Transfer the steak to a cutting board and spread 2 tablespoons of chimichurri sauce on the steak. Cover steak with foil and let rest for 10 minutes while preparing the vegetables for the quinoa bowls.

For the quinoa bowls

1. Cook corn. In the same pan used to sear the steak, add 1 teaspoon olive oil and heat over medium-high heat until oil begins to shimmer. Add the corn. Sauté corn, scraping up any brown bits from the pan, until it is warmed through. Season to taste with salt and pepper. Transfer corn to a plate.
2. Cook peppers. If pan is dry, add another teaspoon of olive oil. Add bell peppers and cook until they are tender-crisp. Season to taste with salt and pepper. Transfer bell peppers to same plate as corn.
3. Cook spinach. To the pan, add the spinach. Sauté spinach until it is wilted. Add 1-3 teaspoons of water to the pan and cover if necessary to help the spinach wilt.
4. Cut steak. Slice the steak against the grain into thin slices and then into bite-sized pieces.
5. Serve. To serve, fill bowls with desired amounts of quinoa, steak, corn, bell peppers, spinach, and avocado. Drizzle desired amount of ponzu sauce on top, and serve with a sprinkle of fresh cilantro leaves.