ASANA
Seated Leg Behind Head Pose - Eka Pada Sirsasana
Extreme External Hip Rotation & Flexion

This pose gives good massage to the organs through pressurizing the abdominal cavity asymmetrically. Getting one leg behind the head is most accessible laying on the back and after working on poses like Pigeon, Frog, and Bound Angle. While laying down you can actively flex your torso lifting your chest and head while pushing one leg back. Until the foot can reach behind the head without too much pressure on the neck one can simply hold the leg and work with the breath to relax deeper into the hip stretch.