Braised Chicken Thighs without seasoning bay

1 medium onion , halved lengthwise and sliced 4 medium new potatoes , cut into 1/4-inch thick slices (about 1 lb.) 2 cups baby carrots 1 1/2 teaspoons salt ,[...]

4 chicken thighs , on the bone with skin 2 stalks celery , chopped in big pieces 2 large carrots , chopped in big pieces (or some mini carrots cut in half) 1[...]