Divide salad greens among 4 large salad bowls. Top each with bell peppers, black beans, and tomatoes. Refrigerate until ready to assemble the rest of the salad.
Place all the ingredients for the pico de gallo into a medium size bowl and toss gently. Refrigerate until ready to serve.
Preheat grill or grill pan to medium high heat. Combine the spices in a small prep bowl. Brush the chicken breasts with olive oil and sprinkle spice mixture on all sides. Grill chicken for about 5-6 minutes on each side or until white all the way through.
Allow chicken to rest for 5-10 minutes, then thinly slice or chop into bite size pieces.
Remove salads from the refrigerator and top with sliced avocado, chicken, and pico de gallo. If desired, serve with a dollop of sour cream or a drizzle of Ranch dressing.