Watt double leads Celtic to the top of the table
Watt scored the second goal of the game from a tempting pass by Twardzik with both players revelling in the opportunity presented to them through injuries.
Neil Lennon made five changes to the side that beat Helsingborg in midweek with Kelvin Wilson, Mikael Lustig, and Paddy McCourt joining Watt and Twardzik in the starting line up.
Back to back away wins in Europe have rendered some cliches redundant with the old story that Celtic always get it tough at Inverness looking dated as the hoops recorded their biggest ever win away to the Highlanders.
Victor Wanyama set the tone for the afternoon in the fourth minute when he powered in a fourth minute header from a corner.
Despite the constant agricultural challenges from the home side Celtic refused to be intimidated with a great piece of play in the 24th minute doubling the lead. Without looking up Twardzik pinged a hopeful path towards Watt who brushed aside the attention of a defender before charging in on goal and clipping a confident shot around Ryan Esson into the net.
Three minutes into the second half Charlie Mulgrew dropped deep to receive a short free kick and clipped a neat left foot effort low into the net.
The partnership of Watt and Gary Hooper was causing havoc in the home defence with Watt netting the fourth from six yards out after Emilio Izaguirre and Adam Matthews had opened up the Inverness defence.
In keeping with the youthful theme Joe Chalmers made his debut with fifteen minutes left to play replacing Emilio Izaguirre.
Caley Thistle pulled back two goals in the closing ten minutes but that won’t take anything away from an impressive performance highlighted by the displays of Watt and Wanyama.
CELTIC: Forster; Lustig, Wilson, Mulgrew, Izaguirre, Matthews, Wanyama, Twardzik, McCourt, Watt, Hooper
Subs: Zaluska, Irvine, McGregor, Bangura, Forrest, Slane, Chalmers