McDonald's Cheddar McMelt is a classic and probably the best sandwhich ever created. It is perfect for mass building also. If you want to gain mass, you should eat "relatively" clean during the week and then pig out and eat whatever you want on weekends. That way, you gain mass without increasing bodyfat much. Eating a couple Cheddar McMelts on your pig out day gives you alost 50 grams of complete protein and 30 artery-clogging but testosterone boosting saturated fats. As long as you eat relatively clean most of the week and do plenty of exercise, you will be fine.
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