The England international scored all three Spurs goals in the 3-1 triumph and said he was happy for his teammates to come through the tough away trip with a win.
"That was a difficult game. A cup tie is always difficult," he told ITV1.
"Away from home it was a great performance from the lads, I am pleased with the win.
"We stuck in and still passed the ball."
Tottenham will now meet Premier League rivals Bolton in the fifth round of the cup after breaking down League One's Leeds.