What is a tantra puja ceremony?

Tantra is a secret practice of transforming every action into a pure action, ie that of a Buddha or God. A puja is a special chanted prayer. A tantra puja ceremony will be prayer in which you praise, worship and do the practice of your particular "Yidam" or deity. In this practice you try and visualise your self as the deity and your world and enjoyments as the deities mandala and offerings, thereby creating only virtue with every action as apposed to non virtue when indulging in pleasures. This practice is however not related to sex, this is an idea that was latter introduced in Europe and was labled Tantra.