Build Muscle or Lose Fat?
I will admit that for years I tried to both at the same time. I have come to the realization that you will have to focus on one or the other, but do not try to do both at the same time: it just leads to frustration.
For fat loss you need to burn more calories than what you eat, while for building muscle you need to eat more calories than your intake. So what is the answer? Eat and work our to lose weight, without losing muscle. Once your body fat is at your target level, you can still start to build more muscle.