Empathy map is a powerful user research tool. It helps analyze and structure the results of user interviews, usability tests, concept testings, etc.
Empathy map puts the aggregated user in the middle and separates the research findings to what users say, think, do, and feel. This helps understand how user behavior aligns with users' opinions, and what sentiments and thoughts arise when using your product.
It is recommended to complete the empathy map after a round of interviews as one of the first steps in data analysis.