The veteran guitarist started recording for the planned album after jamming in his studio and realising the style he was playing reminded him of Rod, who was the singer in his Jeff Beck group in the 1960s.
He explained to Gigwise: "Last week I was in San Francisco to just do some recording with my drummer. "Then there was one point when it went from Jeff Beck over to Rod Stewart, in terms of the direction.
"Immediately I started doing bluesy riffs and a record that was suitable for Rod. Rather than mess about for a week, we decided to get straight to it - and we cut eleven songs and backing tracks ready for Rod."
He added that he is meeting the 'Do Ya Think I'm Sexy?' singer today (25.02.11) to discuss adding vocals to the instrumental tracks he has already laid down.
He said: "I hope things go well, it's the crunch day. We just need to tailor the songs to his voice and then the record is done.''
The 66-year-old rockers previously reunited in 1985 on a cover of 'People Get Ready' by Curtis Mayfield, and have long been hinting at recording more material.
Earlier this month Rod's manager, Arnold Stiefel, said of their latest collaboration: "They have some really clever things planned - it's mind-f***ing stuff."