Marinate the steak by whisking lime juice, olive oil, cilantro, garlic, cumin, chili powder, salt, and black pepper. Coat the steak, cover, and refrigerate for at least 30 minutes.
Cook rice according to package directions and heat black beans in a saucepan for 5 minutes. Prepare corn as needed.
Preheat grill to medium-high. Grill steak for 4-5 minutes per side for medium-rare. Let rest, then slice thinly.
Assemble bowls with rice, black beans, corn, cherry tomatoes, avocado, and red onion. Top with sliced steak and feta, if using.
Garnish with extra cilantro and lime wedges. Enjoy!
Notes
For extra flavor, let the steak marinate longer and serve with your favorite hot sauce!