For all creative roles, including that of the Pastry Chef, your most important criteria for selection are work samples. Next, look into culinary training and proven work experience in your exact environment (restaurants, for instance). Interview candidates should be ready with a culinary portfolio of past creations. Hiring managers may even ask candidates to prepare a pastry dish on the spot, or request candidates to bring samples to the interview.
Use the portfolio and the samples as conversation starters. You’re trying to get a sense of their creativity, their approach to pastry, and their alignment with your pastry chef’s needs. Do you need a chef to do a high-volume pastry? Supervise a team of other chefs? Bake specifically French traditional pastries? Feel free to add your questions to tailor the interview to the exact work environment and responsibilities.
Finally, the interview is a great opportunity to assess the character of your candidates. How well do they handle stress? How would they handle a crisis at work? Do they work well in teams? Since this is still a hospitality role, are they service-oriented? Getting the answers to these questions should be your goal.