The only way to recover from a stall is to get the Angle of Attack (A o A) lower than the critical angel.
If you see your plane heading towards the ground your first reaction will be to pull back but that will only ensure that your aircraft will just keep stalling.
The best way to avoid this is to get to know your airplane and its stall characteristics.
What I have found works best, it to do these manoeuvres away from the ground. Take the remote controlled airplane up high and practice stalls and stall recovery. Make a mental note of how far back you have to pull back on the stick before the plane stalls.
Adding power shortens recovery time as the prop provides additional airflow over the wing as well as increased forward speed and thus airflow over the wings.
No matter what stall you find your self in, straight ahead stalls, turning stalls, power on or power off stalls, spin or snap rolls, the recovery are the same.
Reduce the (A o A) by easing forward on the stick, add power and return to straight and level flight. The best defence against an unwanted stall is understanding why and how they happen. This way you can prevent them happening in the first place.