# Stop the service
sudo /etc/init.d/mysqld stop

# start the mysql server in safe mode
/usr/bin/mysqld_safe --skip-grant-tables &

# Access the mysql console
mysql

mysql> use mysql;
mysql> update user set password=PASSWORD("new-password-here") where User='root';
mysql> GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, SHUTDOWN, PROCESS,
        FILE, REFERENCES, INDEX, ALTER, SHOW DATABASES, SUPER, CREATE TEMPORARY TABLES,
        LOCK TABLES, EXECUTE, REPLICATION SLAVE, REPLICATION CLIENT, CREATE VIEW,
        SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT,
        TRIGGER ON *.* TO 'root'@'localhost' IDENTIFIED BY PASSWORD '*HASHED-PASSWD' WITH GRANT OPTION ;
mysql> flush privileges;
mysql> quit