You need food's energy to drive you through the workout, so a small amount of food in your stomach is best. A lot of people believe that more fat will be burned if they work out on an empty stomach. This simply isn't true. The majority of fat that is burned occurs in the two hours after your workout as your core body temperature returns to normal (this is called EPOC). the key is to stick with it. The reason I say midday is because you then have both food and energy
you cant lose fat where you want to lose fat that is up to your body but HIIT and some good ab work will get you there. remember resistance ppl dont force out 10000's of situps that will create the look of a GH gut in the future.