Heat the olive oil in a large skillet over medium heat.
Add the cubed chicken and season with salt and pepper. Cook until the chicken is browned and cooked through, about 5-7 minutes.
Remove the chicken from the skillet and set aside. In the same skillet, add the diced onion, bell pepper, and garlic. Sauté for about 3-4 minutes until the onion is translucent.
Stir in the diced tomatoes, chicken broth, chili powder, cumin, smoked paprika, and cayenne pepper. Bring to a simmer.
Return the cooked chicken to the skillet, mixing it well with the sauce. Allow to simmer for another 5 minutes, letting the flavors meld together.
Top the skillet with shredded cheddar and mozzarella cheese, covering evenly. Reduce heat to low, cover, and let it cook until the cheese is melted and bubbly, about 5 minutes.
Once the cheese is melted, remove from heat and let cool for a minute.
Serve the skillet hot, topped with sliced avocado and a sprinkle of fresh cilantro.
Notes
Feel free to adjust the spices to your heat preference.