The North Londoners came close to signing Portugal international Moutinho in the summer but missed out on his signature as the proposed deal fell through.
Reports have surfaced Spurs could launch a fresh bid for the 26-year-old in January, with Villas-Boas witnessing him in action during Tuesday night's 2-1 UEFA Champions League defeat to Paris St Germain in the French capital.
The manager is a known admirer of Moutinho after working with the midfielder during his spell at Porto before leaving to take over at Chelsea.
He told the Daily Mirror: "Whenever Porto are close to the place where I am, I go see them.
"I went to see them last season against Manchester City and took the opportunity to go and see them again against PSG.
"It was a tiring trip, but good to see people that are important to me."
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