I teach players to jump off two feet when they expect contact at the basket. When shooting a power layup, as many refer to it, I teach players to square their shoulders to the baseline, rather than to the basket, to use the width of their bodies to protect the ball.
Below is the layup series that I use to teach and practice this shot. Beyond a finishing drill and replicating a finish off an offensive rebound, this is jump landing practice. Many jump training exercises allow the athlete to look at the ground on their landing, but jump landings in competition require the eyes to be focused elsewhere. Also, rebounds are the most common action involved in non-contact ACL injuries (Powell & Barber-Foss, 2000), and many of these injuries occur with a defender within one meter (Krosshaug et al., 2006). These drills practice these landing with eyes directed upward and a defender close to the player on landing.
After the three drills demonstrated, I allow the defense to contest more realistically, and the offense can use fakes and pivots to score; no dribbling. We did this series every practice when I had young post players.