01 - In a small bowl, whisk together the olive oil, lime juice, minced garlic, smoked paprika, ground cumin, salt, and black pepper until well combined.
02 - Place the chicken breasts in a shallow dish or resealable plastic bag. Pour the marinade over the chicken, ensuring each piece is evenly coated. Marinate for at least 10 minutes at room temperature, or refrigerate for up to 2 hours for deeper flavor penetration.
03 - Preheat an outdoor grill or grill pan to medium-high heat, approximately 400°F. Lightly oil the grates to prevent sticking.
04 - Remove chicken from the marinade, allowing excess to drip off. Grill the chicken breasts for 6 to 7 minutes per side, or until fully cooked through and juices run clear. The internal temperature should reach 165°F when checked with a meat thermometer.
05 - While the chicken grills, combine the diced avocados, tomato, red onion, cilantro, and lime juice in a medium bowl. Gently toss to coat all ingredients evenly, then season with salt and pepper to taste.
06 - Transfer the grilled chicken breasts to serving plates. Spoon the fresh avocado mixture generously over each piece. Serve immediately, garnished with additional cilantro or lime wedges if desired.