Rinse rice under cold water until water runs clear. Add rice to a medium pot with chicken broth and 1/2 teaspoon salt. Bring to a boil over high heat, then reduce to low, cover tightly, and simmer for 18 minutes until fluffy, tender, and all liquid is absorbed. Let rest off heat for 5 minutes before fluffing with a fork.

While rice cooks, heat olive oil in a large skillet over medium-high heat. Add ground beef, breaking it into small crumbles with a wooden spoon. Cook for 6-8 minutes, stirring occasionally, until deeply browned with no pink remaining and dark brown edges appear in spots.

Drain excess fat if needed, then sprinkle taco seasoning over the beef. Add 2-3 tablespoons of water to help distribute seasoning evenly. Stir well and cook for another 2 minutes until fragrant and slightly thickened. Remove from heat and let rest for 1-2 minutes.

In a small saucepan, warm black beans over medium heat with ground cumin and garlic powder. Stir gently and heat for 3-4 minutes until warmed through. If using frozen corn, warm it in the microwave for 1-2 minutes; if using canned corn, simply drain well.

Spoon a generous base of rice into each serving bowl. Add seasoned beef on one side and black beans on the other. Top with corn, diced tomatoes, shredded lettuce, and cheddar cheese in colorful rows.

Finish with your favorite salsa, fresh cilantro, and a generous squeeze of lime juice. Serve immediately.