The three-times grand slam champion's form has improved with each match at the $A1 million ITF mixed team competition and on Saturday, she was irresistible.
Hantuchova's Slovak side were surprise finalists after they were asked to step in when already-qualified Australia pulled out on Friday due to an injury to Alicia Molik.
But Hantuchova was unable to make the most of this second chance, crumbling in the face of some power hitting.
Not only was Davenport powerful, but she was deadly accurate and made no unforced errors throughout the 51 minute match at the Burswood Dome.
"I served a lot better than I felt I did earlier this week," she smiled courtside afterwards, "and I had to.
"I had a feeling she would play better against me than she had been playing and she did."
Davenport has now won on all three occasions the pair have met.
The U.S. are chasing a number of Hopman Cup records - the first nation to win successive championships; the most wins of any nation - three - and, for Blake, the chance to join Spain's Arantxa Sanchez Vicario as the only two-time winners.