Prepare the Chicken:
Combine chili powder, cumin, smoked paprika, garlic powder, onion powder, salt, and pepper. Rub this spice mixture generously over the chicken breasts.
Heat 1 tablespoon of olive oil in a large skillet over medium-high heat. Cook the chicken for 6-7 minutes per side until caramelized and the internal temperature reaches 165°F.
Let the chicken rest, then shred it using two forks. Toss the shredded chicken with ½ cup of enchilada sauce.
Make the Cauliflower Rice:
If using a whole cauliflower, pulse florets in a food processor until they resemble rice grains. Heat the remaining tablespoon of olive oil in a skillet over medium heat. Add the cauliflower rice, garlic powder, salt, and pepper. Cook for 5-7 minutes, stirring frequently, until the cauliflower rice is tender but still has a slight bite and is lightly golden.
Assemble the Bowls:
Divide the cauliflower rice evenly into four bowls. Top each with the saucy shredded chicken and drizzle with the remaining enchilada sauce.
Sprinkle each bowl with shredded cheddar cheese and place under the broiler for 2-3 minutes, or until the cheese is bubbly and slightly browned.
Garnish with diced red onion, sliced avocado, fresh cilantro, and a dollop of sour cream or Greek yogurt. Serve with lime wedges on the side.