Preheat the oven to 350.
Lay out chicken pieces and sprinkle both sides with salt and pepper.
Cover bottom of skillet with olive oil and turn on medium setting.
Brown chicken pieces for 4-5 minutes on each side.
Remove and sprinkle with thyme and sage.
Pour out most of excess oil and then place skillet back on burner.
Put chicken broth and minced garlic in skillet and stir, scraping bottom of pan. Let cook on medium low heat for a few minutes.
Place onion and carrot slices in bottom of greased casserole dish.
Pour chicken broth with garlic over the onion and carrots and stir.
Place chicken pieces on top of carrots and onion.
Pour jars of tomato sauce over the top.
Bake at 350 for 1 1/2 hours.