Present continuous tense is used to describe an action that is going on in the present time. The given sentence shows a question about an ongoing event. So we will use the present continuous tense. The syntax for present continuous tense (in interrogation) is: is/am/are + subject + verb (ing). 'I' & 'You' are exceptional cases which in spite of being singular subjects take the verb of plural subjects. Therefore, the correct option is: are you enjoying.