Change what you eat. Not how much. So many people get calorie reduction wrong that they push their body into survival mode to protect against what it perceives to be starvation. The result is their metabolism slows to the point that stubborn fat becomes even more stubborn. It can therefore be more effective to forget calorie counting (who has the time and patience for that anyway?) and just eat healthier and move more.
Lean meats, poultry, fish, dairy, nuts, seeds, fruit and vegetables. Doesn't get more simple than that.
For you workouts, shorter but more intense circuits are far better than boring, steady-state cardio. Sprints, jumping rope, callisthenics, and lifting weights are all winners.