In order to create a one-to-many mapping in Hibernate/JPA using Spring Boot and MySQL, you will need to follow these steps:

1. Create a MySQL database and tables for the entities you want to map.
2. Create a Spring Boot project and add the required dependencies for Hibernate/JPA and MySQL.
3. Create entity classes for the tables you created in step 1, with appropriate annotations for mapping the fields to the columns in the database.
4. Create a repository interface for each entity class, extending the JpaRepository interface and specifying the entity class and primary key type.
5. In the entity class representing the “one” side of the relationship, use the @OneToMany annotation to specify the relationship and the @JoinColumn annotation to specify the foreign key column.
6. In the entity class representing the “many” side of the relationship, use the @ManyToOne annotation to specify the relationship and the @JoinColumn annotation to specify the foreign key column.
7. Create a service layer to handle business logic and a controller layer to handle requests and responses.
8. Test the mapping by creating and saving instances of the entities and verifying that the relationship is persisted correctly in the database.

Note that this is just a high-level overview of the process and there may be additional steps or considerations depending on your specific use case.