The former Blues boss reiterated his love for the club he managed for more than three years before his sensational departure in September.
But he is desperate to meet them in Champions League combat next season and knock them out of Europe.
"If I play them in the Champions League, I want to go there and kill them - that's my message."
Mourinho was replaced by Avram Grant, who had originally been brought to Stamford Bridge as director of football.
He refused to express an opinion on his successor, saying: "I feel nothing for him, I feel everything for the club, but not for him personally.
"I left and for five months you couldn't get a bad word from me in relation to the club and you cannot do it in the future too."
Mourinho's departure was shrouded in mystery, with the build-up dominated by rumours of a falling out with billionaire owner Roman Abramovich.
But he revealed he and the Russian had kept in contact and were on good terms.
"I think it was last week that I spoke with people from the club," he said.
"I was speaking with Mr Abramovich and (chief executive) Peter Kenyon because we still keep in touch.
"I was telling them I wish them always good, I wish them always to succeed, I wish them always to win."