Step 1: Marinate the Chicken

1. In a bowl, mix olive oil, lime juice, chili powder, smoked paprika, cumin, garlic powder, onion powder, salt, and pepper to create a marinade.
2. Add the chicken to the marinade, ensuring each piece is well coated. Cover and refrigerate for at least 30 minutes, or up to 4 hours for deeper flavor.

Step 2: Prepare the Rice

1. Rinse the rice under cold water until the water runs clear to remove excess starch.
2. In a medium saucepan, heat olive oil over medium heat. Add the rice and toast for 2-3 minutes, stirring frequently.
3. Add water or chicken broth and salt. Bring to a boil, then reduce the heat to low, cover, and simmer for 15-20 minutes (or 40-45 minutes for brown rice) until the liquid is absorbed.
4. Remove from heat and let sit, covered, for 5 minutes. Fluff with a fork, then stir in lime juice and cilantro. Set aside.

Step 3: Cook the Beans

1. Heat olive oil in a small saucepan over medium heat. Add minced garlic and sauté for 30 seconds until fragrant.
2. Add black beans, cumin, chili powder, salt, and water or chicken broth. Stir and simmer for 5-7 minutes, until heated through. Remove from heat and set aside.

Step 4: Grill the Chicken

1. Preheat your grill or grill pan to medium-high heat. Lightly oil the grates to prevent sticking.
2. Remove the chicken from the marinade and grill for 4-5 minutes per side, or until the internal temperature reaches 165°F (75°C).
3. Let the chicken rest for 5 minutes, then slice into strips or bite-sized pieces.

Step 5: Assemble the Bowls

1. Start with a base of cilantro-lime rice in each bowl.
2. Add a layer of black beans, followed by shredded lettuce.
3. Top with grilled chicken, diced tomatoes, corn, and avocado.
4. Sprinkle with shredded cheese and add a dollop of sour cream or Greek yogurt.
5. Garnish with salsa, pico de gallo, and tortilla chips if desired. Serve immediately.