If a good morning and a back squat had a baby, it would be the Kang Squat. This is a movement that works the posterior chain and will really benefit your other barbell lifts like the deadlift and back squat.
As you can imagine, the Kang squat works all the muscle groups that a back squat does, but you have the increased benefits of hitting those hamstrings and back muscles because of the good morning portion of the movement.
This movement should be looked at as an accessory exercise. Therefore, you don't really need to push big weight to get the most out of this lift. Keeping proper form and really solid movement patterns is more important.
To begin: place the barbell on your back like you would for a good morning. Hands should be placed on the bar outside of the shoulders and feet should be between hip and shoulder-width apart depending on your personal preference.
With a flat back and slight bend in the knee, hinge at the hips like you're performing a good morning. Again, you're looking to get your torso close to parallel to the floor.
From this position, bend your knees and drop your hips back into a full-depth squat. Make sure you spine stays straight throughout.
Now, we come back the way we came by straightening the knees, raising the hips, and coming into the good morning position where the torso is parallel to the floor.
Return to standing by raising the torso like you would to complete a good morning. This is one rep.