First I would find out why the Soldier failed to complete the corrective training. If the Soldier blew you off I would suggest that you counsel him again for failure to follow an order. I encourage you to make sure you have your facts together and that you are executing from an unemotional and professional position. By doing this you ensure you are doing the right thing and when your chain of command looks at your actions and recommendation they will be more likely to support you. The last thing you want your chain of command to see this as a power struggle or to think that you are acting in an unprofessional or inexperienced manner.
Make sure the counseling contains the standard derogatory counseling (Magic Statement). Inform the Soldier in the counseling statement that failure to properly execute the corrective training to standard will result in a recommendation for punishment under the UCMJ. I would then give him a prescribed time frame to finish the essay and would also recommend that he be required to prepare a 10 minute class on why integrity and dependability are important. Have him give the class to you.
If the Soldier performs to standard, case closed. If he does not perform to standard, he has chosen to ignore the second chance you have given him. If the Soldier fails to complete the corrective training, provide another counseling statement and recommend an Article 15.
Read The Mentor: Everything you need to know about leadership and counseling for more information about Counseling, Leadership, Corrective Training, and Separations in the Army.