You didn't gain the extra 90 pound in a year and so, I'm not sure you can loose them in a year.
Over all it doesn't matter how much weight you want to use or in how much time, most diets whether you want to loose 5 pounds or a 100 are the same - eat less (around 1500 cal a day) exercise 3-7 times a week for at least 30 minutes. Keep away from "empty calories" (processed food, junk food, white sugar and so on).
That's basically it. Do that till you loose all the weight you want to loose, whether this takes 6 months or 2 years. Any other diets that are more extreme are not something most people can stick to. If you want to speed the process exercise more.
It's hard work, but if you can pull it off, you will loose all the weight in a healthy way.
