The daily puja at Kadampa Buddhist Centers is Heart Jewel, which is a Guru yoga of Je Tsongkhapa combined with the condensed sadhana of his Dharma Protector and a short mediation on Lamrim.
This puja includes two practices revealed by the Wisdom Buddha Manjushri. The first is a special Guru yoga in which we visualize our Spiritual Guide as Je Tsongkhapa, who himself is a manifestation of Manjushri.
By relying upon this practice, we can purify negativity, accumulate merit, and receive blessings. In this way, we will naturally accomplish all the realizations of the stages of the path of Sutra and Tantra, and in particular we will attain a very special Dharma wisdom.
RELYING UPON THE DHARMA PROTECTOR
The second practice is a method for relying upon the Dharma Protector Dorje Shugden. Through this, we can overcome obstacles to our practice and create favourable conditions so that we can nurture and increase our Dharma realizations.
If we rely upon the Dharma Protector Dorje Shugden sincerely, our faith in Je Tsongkhapa will naturally increase and we will easily gain experience of the pure Buddhadharma transmitted directly to Je Tsongkhapa by the Wisdom Buddha Manjushri.
These two practices are the very essence of the New Kadampa Tradition of Mahayana Buddhism. If we practice them regularly and sincerely, we will reap a rich harvest of pure Dharma realizations, and eventually come to experience the supreme joy of full enlightenment.
An extensive explanation of this sadhana can be found in the book Heart Jewel, by Geshe Kelsang Gyatso.