Which Buddhist Meditation is comparable to Transcendental Meditation?

A friend of mine was practicing zazen for many years. They started to get discourage with their practice and started to explore transcendental mediation. Now, they claim their progress with TM is far better in a matter of weeks when compared to zazen. I was wondering if there is an equivalent to TM in any of the Buddhist traditions? If so, what are the basics and framework of the parallel type of meditation?