I hate to be the one to burst your bubble but you are going to have a difficult time doing both at the same time.
In order to build muscle you must feed your muscle with high calorie and high protein foods to bulk up.
In order to burn fat you must eat low calorie, low fat foods.
Can you see that this is basically complete opposites? Don't be frustrated though there is a way to accomplish both but you must focus on one first and then focus on the other.
Here is how you do it.
Step # 1 Build Muscle I first suggest that you work on building muscle.
Focus your attention for 2 months on nothing but bulking up.
Lift heavy weights at least 4 to 5 times a week and use high calorie, high protein foods to help achieve your desired muscle gain.
After 2 months of this then move on to step two: Step # 2 Lose Fat As mentioned above start this plan with the focus on building as much muscle as possible in two months.
Then in order to lose fat I suggest for the next two months you focus your attention on low calorie, low fat foods while toning down your work out sessions to 3 to 4 times per week and adding in cardio the other 3 to 4 days.
What this will do for you by continuing to work out is to maintain the muscle bulk you built up during the past two months but you will also start to lose the fat in your body by eating lower calorie and lower fat foods.
Cardio will help burn the calories and fat quicker and you will start to see the results you are looking for.
Then rinse and repeat the process.
In closing: The plan is simple: First 2 months concentrate your efforts on bulking up with heavy weights 4 to 5 times a week while eating high calorie and high protein foods.
The next 2 months concentrate your efforts on light lifting, lower calorie and lower fat diet with 3 to 4 days of cardio incorporated.