Novel technologies wear traditional expectancies of what molds the ‘professions’ and the ‘expert’. Interdiscursive performance as part of critical genre analysis permits examination of how YouTubers set up professional expertise. Vlogging is an example of a professional genre, rich in interdiscursivity. This paper uses Bhatia's (2017) framework of Critical Genre Analysis (CGA), which centers on three interdiscursively correlated elements of professional expertise – discursive competence, disciplinary knowledge and professional practice.