The England international defender has regularly found himself on the bench in recent weeks, with Cesar Azpilicueta preferred at left-back.
But Mourinho has moved to praise Cole's attitude in training as he bids to reclaim his place in the Chelsea starting XI.
"His attitude is phenomenal, as always," he said. "He has the same attitude today that he had when he trained with me for the first time.
"Even through the difficult period, yes. Ashley's attitude is an example.
"Azpilicueta is playing fantastic."
Mourinho went on to apparently rule out too much action in the January transfer window, despite being linked with moves for Real Madrid defender Fabio Coentrao and Porto striker Jackson Martinez.
"No. No. I don't want Portuguese players" he said. "I always had them but, at this moment, it's enough.
''I don't have them now. Only Hilario, the remaining one. But we don't need. We don't need.
''In the January market we're not going to buy any striker, so we will go through to the end of the season with Fernando (Torres), Samuel (Eto'o) and Demba (Ba). Nobody goes in. Nobody goes out.''
Mourinho is hoping his charges can bounce back from a midweek 1-0 UEFA Champions League defeat in Basel with victory over high-flying Southampton on Sunday.
"I never tolerate a loss," he continued. "But I have to live with it. We will try everything not to repeat it.
"We analysed their individual match performances and today's (Friday) training session was very good.
"Now is the time for the squad. It's time for everybody to feel that they have a chance."
But the former Real Madrid coach is aware of the challenge posed by Mauricio Pochettino's side, who would leapfrog Chelsea in the table with a victory.
"Southampton are very compact and solid," he added. "They are doing well. They will have a very good season."
