A 3-1 win over Dnipro Dnipropetrovsk on Thursday gave the Premier League outfit a 3-2 aggregate victory and booked their place in the last 16.
Emmanuel Adebayor scored a crucial second-half brace after the Ukrainians had opened the scoring at White Hart Lane.
Sherwood wants to see his side build on their victory as they aim to erase the six-point deficit to fourth-placed Liverpool in the Premier League.
"It's a big platform for us, we started very well. I can only talk since I've been here but it's been brilliant in the Premier League," he said.
"We've struggled in cup competitions but on the back of a poor result at Norwich we should really be bouncing into that game against Cardiff on Sunday.
"That's what we're looking for, a platform, and we believed we could win this game today and turn the tie around.
"We've actually done that, we've come out and done it. It's all right talking about it but you have to go out and do it. We've done that and we're looking forward to the next game on Sunday."
Roman Zozulya's header made it 2-0 to Dnipro on aggregate in the 48th minute of the second leg, before Tottenham's response started.
Christian Eriksen's dipping free-kick pulled one back for Spurs before Adebayor made an impact after Zozulya had been sent off.
He poked an Eriksen cross in before a wonderful touch and finish sealed the tie for Tottenham.
Sherwood hailed his side's ability to come from behind after looking set for an earlier-than-expected exit.
"It is a good platform, it is a good learning curve and it is something we can point to in the future if we do go behind, we have to give everything," he said.
"This club won't accept anything less than that. We have to give everything even if we're out of the game.
"We have to still try our best to get some pride out of it and that's what I try to instil in them and it's fantastic we were able to turn that around tonight."
