Stuart Lancaster, deprived of 18 players who were involved in Saturday's Premiership final, opted to mix youth and experience despite the game being a non-capped Test match as the likes of Christian Wade and Tom Johnson came into the side for their first caps.
The Barbarians fielded a strong line up that included former England captain Mike Tindall, former All Black Mils Muliaina and World Cup winner Stephen Donald.
Owen Farrell enjoyed a mixed day with the boot, converting seven of eight conversions but missing with a couple of penalties in the opening exchanges.
But the real hero for England was Ashton whose two tries, along with one for the returning Dylan Hartley, helped the Red Rose into a 22-7 half-time lead.
After the break Ashton's third cancelled out Mils Muliaina's second for the Baa-Baas before Wade crossed for his first try in England colours.
Two scores from Tindall and Pelu Taele closed the gap but a late flurry from Richard Wigglesworth and a double from London Irish flyer Jonathan Joseph sealed a comfortable victory.