Cut the chicken breasts into bite-size pieces.
Open the diced tomatoes and tomato sauce.
In a large stockpot or Dutch oven, add the chicken pieces, the diced tomatoes with their juices, tomato sauce, chili powder, minced onion, minced garlic and bring to bubbling. Stir in the chicken stock and return to bubbling over high heat.
Once bubbling, stir in the lentils, cover with a tight fitting lid and let simmer for 20 to 25 minutes, or until the lentils are tender. Season with salt and pepper to taste.
Prepare the salad.
Serve Chicken & Lentil Chili with sour cream and parsley garnish, with side salad.