Cardio. It's impossible to target fat in one specific area of your body as you only lose fat all over your body through cardio - e.g. running, swimming.
I have the same problem regarding stomach fat, its more a beer belly. as I will be at home for summer I will eat healthier and have proper meals in addition to doing cardio. I'm getting a stand for my punching bag and an spinning bike and gonna blitz it over the summer.