Get near a lava area that is next to a road. Select your fists, and wait for a vehicle to drive past. Either kill the driver and exit the vehicle, or do the following with the driver still inside. Use your melee attack to push the vehicle into the lava, and wait for it to explode to get the "Out Of The Frying Pan" achievement. You can also get the car into the lava by sprinting into it or using the Stomp ability. Note: Driving the car towards the lava and jumping does not count.