Mix together the chili powder, cumin, garlic powder, onion powder, salt, and pepper in a small bowl. Rub this spice mixture all over the flank steak, coating both sides evenly. Drizzle with 1 tablespoon of olive oil and let it marinate for at least 15 minutes at room temperature. If marinating longer than 30 minutes or up to 4 hours, refrigerate for food safety, then bring to room temperature for 10 minutes before cooking.

Heat a grill pan or heavy skillet over medium-high heat until very hot. Cook the steak for 4-6 minutes per side without moving it. For medium-rare, aim for an internal temperature of 130-135°F; for medium, 140-145°F; for medium-well, 150-155°F.

Transfer the cooked steak to a cutting board and let it rest for 5-10 minutes. After resting, slice thinly against the grain at a slight angle for maximum tenderness.

While the steak cooks, prepare the vinaigrette by combining lime juice, olive oil, cilantro, garlic, honey, salt, and pepper in a blender or jar with a tight lid. Blend for 20-30 seconds until bright green and smooth, or shake in a jar for 45-60 seconds until fully emulsified.

Divide the cooked rice among four bowls, then arrange the sliced steak, corn, black beans, avocado, and cherry tomatoes on top. Drizzle generously with the cilantro-lime vinaigrette and serve immediately.