I'm going to second the "quit smoking" suggestion. Everyone that I've ever known who quit smoking gained weight, 20 pounds minimum. Actually at 93 pounds she's not that much underweight. I'm 5'-2" and don't cross into the underweight category until I get down to less than 99lbs. So at 5'-3" she's probably only 10-15 pounds underweight.
As far as bars go I like the Pure Protein bars, they are about 200 calories also. The Chocolate Deluxe taste like chocolate covered Tootsie Rolls to me. The other thing I would suggest she try are peanut butter, whole grain bread, beef, whole milk, pork, lamb and real butter.
Starting weight: 244.6 lbs. 10/01/09
Pounds lost: 80.6 lbs
Current weight: 164 lbs
Goal weight: 120 lbs
Weight to go: 44 lbs
Goal Date: 1/1/13