Pandev signed for Inter this week after winning his legal battle to terminate the contract, having been frozen out for six months.
"He is selected (against Chievo) and will play from the beginning even if I don't know for how long," Mourinho said.
"Goran is a modern striker. He's exceptional, allowing us to play with two or three up front. He's a champion who adapts himself to all tactical schemes.
"We worked together yesterday and I am explaining to him how he will have to play for us. Goran will have to recover the dynamism and intensity of his play but he'll quickly adapt in my opinion. It will not take hard work."
Asked if he is following the example he set with Wesley Sneijder by throwing Pandev in at the deep end, Mourinho said: "Wesley came from a team in which he played regularly and he arrived with minutes and match fitness in his legs.
"It's different with Goran, seeing that he has played only one game in five or six months only with his national team. The psychological aspect allows you to work miracles. Pandev's great motivation and his desire to return to first team football can make the difference.
"He's not yet on top, but he has told me that he is ready to play for however long is necessary."