In a small bowl, whisk together the chili powder, ground cumin, smoked paprika, garlic powder, onion powder, dried oregano, coarse sea salt, and black pepper.

Spread half of the sliced bell peppers and onions across the bottom of a 6-quart slow cooker crock. Drizzle with 1 tablespoon of olive oil.

Place the whole chicken breasts on top of the pepper layer. Rub chicken with the remaining 1 tablespoon of olive oil and minced garlic, then coat generously on all sides with the homemade fajita seasoning blend.

Scatter the remaining bell peppers and onions over the seasoned chicken. Squeeze the fresh lime juice over everything.

Cover with the lid and cook on LOW for 5 to 6 hours (or on HIGH for 2.5 to 3 hours) until the chicken breasts are ultra-tender and reach 165°F.

Remove chicken breasts to a cutting board, let rest for 5 minutes, then slice into thin strips. Return the sliced chicken back into the slow cooker and toss with the peppers, onions, and flavorful pan juices.

Spoon sizzling chicken and peppers into warm flour tortillas. Top with fresh guacamole, pico de gallo, sour cream, and fresh cilantro. Serve with lime wedges.