From the 737 FCTM:
If normal pitch control inputs do not stop an increasing pitch rate, rolling the
airplane to a bank angle that starts the nose down should work. Bank angles of
about 45°, up to a maximum of 60°, could be needed. Unloading the wing by
maintaining continuous nose-down elevator pressure keeps the wing angle of
attack as low as possible, making the normal roll controls as effective as possible.
With airspeed as low as stick shaker onset, normal roll controls - up to full
deflection of ailerons and spoilers - may be used. The rolling maneuver changes
the pitch rate into a turning maneuver, allowing the pitch to decrease. Finally, if
normal pitch control then roll control is ineffective, careful rudder input in the
direction of the desired roll may be required to induce a rolling maneuver for
recovery.
Only a small amount of rudder is needed. Too much rudder applied too quickly or
held too long may result in loss of lateral and directional control. Because of the
low energy condition, pilots should exercise caution when applying rudder.
The reduced pitch attitude allows airspeed to increase, thereby improving elevator
and aileron control effectiveness. After the pitch attitude and airspeed return to a
desired range the pilot can reduce angle of bank with normal lateral flight controls
and return the airplane to normal flight.