This may be the hardest quad-dominant exercise you'll ever do. Lifters spend most of their time moving weights "fast" and getting into the hole quickly. Make yourself slow down and control the tempo of your lift, even if it means your 400-pound squat becomes a 185-pound one.
Tempo squatting stimulates hypertrophy in your slow-twitch, type-I fibers that are often neglected.
Set up with the weight considerably lighter than you'd use for your regular squat.
Set a timer for 40-60 seconds and keep constant tension in your lower body by pulling yourself down into the hole and not pausing at any point during the lift.
Count 3 seconds up and 3 seconds down throughout the entire minute and you'll feel a quad burn like never before.