Preheat the oven to 350 degrees F (175 degrees C). Grease a baking pan.
Season chicken breasts with salt and pepper and lay out in the baking pan. Spread salsa across chicken breasts and sprinkle with Cheddar cheese.
Bake in the preheated oven until chicken is no longer pink in the center and the juices run clear, 25 to 30 minutes. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C).
Spread 1 tablespoon guacamole on each chicken breast to serve.
