Sniper Elite: Resistance

Near the tank (or rather, the easiest one to take out) in mission 8 (End of the Line), there's a network of trenches you can use to slip by enemy reinforcements. It's also a really good idea to clear out as many enemies as you can from the sniper nest near the beginning of the mission, so you have fewer bad guys to contend with. Take the trenches, find your way close to the tank, and you'll likely find a nearby Panzerfaust launcher and satchel charge. Make sure the perimeter is clear, then approach the tank from the rear. You can either pop it with the Panzerfaust then snipe its red glowing innards until it explodes, or sneak up on it and plant a satchel charge, finishing it with the Panzerfaust or your rifle. Either way, it'll blow up real nice and you'll unlock this for your efforts.