Prepare the Marinade: In a medium bowl, whisk together lime juice, olive oil, chopped cilantro, minced garlic, ground cumin, chili powder, and salt and pepper to taste.

Marinate the Steak: Place flank steak into a resealable plastic bag, pour the marinade over it, seal, and refrigerate for at least 30 minutes or up to 4 hours.

Cook the Rice: Prepare rice according to package instructions, fluff with a fork once cooked.

Heat the Black Beans: Warm black beans in a small saucepan over medium heat for about 5 minutes, seasoning if desired.

Prepare the Corn: Cook fresh corn in boiling water for 3-4 minutes, or heat frozen corn in the microwave.

Grill the Steak: Preheat the grill, remove steak from marinade, and grill for 4-5 minutes on each side for medium-rare.

Rest and Slice the Steak: Let the steak rest for 5-10 minutes, then slice it against the grain into thin strips.

Assemble the Bowls: Start with a base of rice, add black beans and corn, layer the sliced steak on top, and finish with fresh veggies.