"We talked about Beethoven a lot on that tour," she says. "Playing the Kreutzer was my first prolonged exposure to his music, night after night, and I remember thinking what a dream it would be if I could play all ten of the sonatas with Michael."
Dreams have come true; she's paired her up, once again, with a pianist who she feels shares her sense of musical intuition: "Sometimes in rehearsal I'm so inspired, listening to his playing, that I forget to come in."
The sonatas that Hristova and Houstoun will deliver were written between 1798 and 1812. They range from Beethoven's early period, in which you sense a young man breaking free from the influence of Haydn to become a mature composer who, as deafness gradually overtook him, was on the brink of new musical discoveries.
"There's such a sense of joyousness in those very first sonatas," Hristova says. "And it's quite a journey through to Opus 96, in which there's only one fortissimo marking. This is a completely introspective and reflective piece, and all the more powerful for being so.
"For us violinists, it's our only taste of Beethoven about to launch into the great works of his last years, unless we play his late string quartets."
Auckland is the final stop on a gruelling tour, with 16 concerts in 17 days.
"It will be much more physically demanding than in 2008, because it's more condensed," Hristova says. "We do have three days off, but on two of the other days there are two concerts scheduled. We'll certainly be working on our focus and concentration as well as physical stamina, but Beethoven's magnificent music is the perfect inspiration for us."
Those who thrilled to the sound of her 1655 Amati violin on those earlier visits will be happy that it is undertaking this Beethoven adventure with her.
"It has such a range of colours and tone, as well as a power that Amatis are not always known for and, if I dig into it and ask a lot of it, it always gives it to me."
Lowdown:
What: Bella Hristova and Michael Houstoun
Where & when: Auckland Town Hall; Friday, September 8 at 7.30pm and Saturday, 9 September at 3pm and 7.30pm.