Marinate the Steak: Whisk together lime juice, olive oil, cilantro, garlic, cumin, chili powder, salt, and pepper. Add the flank steak, ensuring it's fully coated, and refrigerate for 30 minutes to 4 hours.

Prepare Rice and Beans: Cook the rice according to package instructions until fluffy. Heat the black beans in a small saucepan for about 5 minutes until warmed through.

Grill the Steak: Preheat your grill to medium-high heat. Remove the steak from the marinade, letting excess drip off. Grill for 4-5 minutes per side for medium-rare. Let it rest for 5-10 minutes before slicing.

Assemble Bowls: Divide cooked rice among bowls. Top each with black beans, corn, cherry tomatoes, avocado, and red onion. Lay sliced steak over the top and garnish with cilantro and lime wedges.