The Brumbies' willingness to run the ball from their own half was rewarded with a four try bonus point at just the 30th minute mark.
The foundations for their attack was built on the back of ruthless defence, constantly driving the Rebels backwards and forcing errors.
It took the Brumbies just three minutes to get on the board, Toomua slipping under Tom English out wide after more than a dozen phases.
The Rebels replied with a penalty, before Brumbies fullback McCabe burst over for a 12-3 lead in the 14th minute.
Toomua picked up his second two minutes later courtesy of a White linebreak, before prop Scott Sio scored his first try of the season in the 30th minute to secure the bonus point.
The Brumbies picked up where they left off after halftime, lock Sam Carter burrowing over for a 32-3 lead.
The Rebels finally got the upper hand in an epic scrum battle, and Brumbies prop Ben Alexander was yellow carded with 13 minutes to go.
The Rebels made the most of their numerical advantage with a try to captain Scott Higginbotham, but the Brumbies would cap off a great night with a try to Leon Power.
Goalkicker Christian Lealiifano continued to struggle with the boot, only managing three from seven, while captain Ben Mowen went off with a cut under his eye in the 50th minute.
The win moves the Brumbies up to fourth spot on the log, and three points behind the Australian conference leading Waratahs.
The Rebels on the otherhand have slipped back to 13th spot going into the break for the June Tests.
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-AAP