In a large bowl, combine the sliced flank steak with 1 tablespoon olive oil, chili powder, cumin, smoked paprika, oregano, salt, and black pepper. Toss thoroughly to coat every piece, then let it sit at room temperature for 15-20 minutes. For deeper flavor, marinate refrigerated for up to 2 hours.

Heat the remaining tablespoon of olive oil in a large cast-iron skillet or heavy pan over medium-high heat. Add the sliced bell peppers and onion, cooking for 5-7 minutes until tender-crisp. Add the minced garlic during the last minute, then transfer the vegetables to a plate.

Using the same skillet, arrange the marinated steak in a single layer and cook for 2-3 minutes per side for medium-rare, or 3-4 minutes per side for medium. Avoid moving the meat around during cooking.

Divide the cooked rice among four bowls, top each with equal portions of seared steak, sautéed peppers and onions, shredded cheddar, salsa, and sliced avocado. Garnish with fresh cilantro and serve immediately with lime wedges.