Start by patting the chicken breasts dry with paper towels. In a large bowl, whisk together olive oil, cumin, smoked paprika, chili powder, garlic powder, onion powder, dried oregano, salt, pepper, and lime juice. Add the chicken breasts, turning to coat evenly. Cover and marinate in the refrigerator for at least 20–30 minutes.
While the chicken is marinating, cook brown rice or quinoa according to the package instructions. Once ready, fluff the grains with a fork and season lightly with salt if desired.
In a medium saucepan, heat 1 tablespoon olive oil over medium heat. Whisk in the flour, cooking for 30–60 seconds until it forms a smooth paste. Stir in chili powder, cumin, garlic powder, onion powder, oregano, smoked paprika, black pepper, and salt. Gradually whisk in chicken broth, then add tomato paste. Bring to a gentle simmer, cooking for 5–7 minutes.
To cook the marinated chicken, choose your preferred method: grill, pan-sear, or bake. For grilling, preheat the grill to medium-high, lightly oil the grates, and grill the chicken for 5–7 minutes per side until cooked through. For pan-searing, heat oil in a skillet over medium-high heat and cook chicken for 6–7 minutes per side. For baking, preheat the oven to 400°F and bake for 20–25 minutes.
Once cooked, let the chicken rest for 5 minutes, then dice or slice the chicken into bite-sized pieces.
In a large mixing bowl, place the chicken and pour about 1 to 1.5 cups of warm enchilada sauce over the chicken. Toss gently until well coated.
Prepare the bowl components by arranging the black beans, corn, diced bell pepper, diced red onion, tomatoes, avocado, cilantro, Greek yogurt, and optional toppings in separate small bowls.
For each bowl, start with ½ to ¾ cup of cooked grains as the base. Spoon a portion of enchilada chicken over the grains, then add black beans, corn, diced bell pepper, red onion, and tomatoes. Top with Greek yogurt and cheese if using, avocado, and cilantro.
Serve immediately while warm, drizzled with any reserved enchilada sauce and a squeeze of lime juice.