Some common biceps exercises fall short in maintaining tension throughout the movement, but kettlebell curls are an exception. Try this pistol variation.
Kettlebell Pistol Hammer Curl
This variation also helps to emphasize an elongated eccentric contraction, which causes lots of microtrauma that's essential for muscle growth.
As a result of the high tension, kettlebells also produce an occlusion–type effect, whereupon the restricted blood flow acts as another kind of hypertrophy stimulus.
This move specifically targets the brachialis and brachioradialis in the top portion of the movement. Give it a shot!