What is your recommendation for the fastest legitimate way to lose body fat?

Diet and Exercise: The goal is to burn more calories than you consume. Watch your diet-eliminate junk food and don't over eat. Consider liquids as well-soda, alcohol, etc contains a lot of calories. Exercise multiple times a week. If you find an activity you really enjoy you'll be more likely to engage in that activity. Avoid fad diets that could prevent you from getting adequate nutrition. Make healthy choices!

Weight loss: Rapid weight loss and dieting is not particularly effective, especially long term. Usually, when the dieting stops, one gains the weight right back, and then some. In general, one should not expect to lose more than one or two pounds per week. Any more than that and you are probably not losing fat. It takes getting rid about 3500-4000 calories to lose one pound. Slow and steady is best. Good luck.