The goblet squat is a beneficial exercise to teach squat mechanics with a focus on hip abduction (external hip rotation) and ankle dorsiflexion (the ability for your ankle to flex up).
Using a dumbbell or kettlebell, the client can create a shift in the center of mass, thus allowing for a more upright torso and deeper position.
I also use the goblet squat as a warm up to increase the mobility of ankles and hips.
Here is a fun twist on the traditional goblet squat using bands and heal elevation to target the glutes. You can use a kettlebell or dumbbell for this exercise and make sure to place the band about 1-2 inches above your knees and push out.
If you are unable to push the band out with good squat form user a light resistance band or remove the band and only use the plates under your feet. I am only using 25# plate with a 50# dumbbell