Giroud had started only two Premier League games this season with the last coming in November.
With Tammy Abraham lacking match fitness and Michy Batshuayi out-of-form, the Frenchman was given a starting berth by Frank Lampard.
It took Giroud only 15 minutes to send a message to Lampard that he can be Chelsea's main striker.
The French World Cup winner fired low past Spurs keeper Hugo Lloris for the Blues’ opener after the recalled Ross Barkley hit the post.
Speaking to the media after the game, the former Arsenal forward said Chelsea showed great character to get back to winning ways after a home defeat against Manchester United last Monday.
"It was a very important game for us today,” the 33-year-old said.
“I want to talk about the team spirit. We've shown great character today. We knew it was maybe a kind of turning point. We lost a bit of confidence.”
“It was nice to bounce back and get this win, a hard win against a rival, so I feel relieved today.”
"I was lucky the ball came back after hitting the post and I tried to finish. It was a good feeling for me, a good moment and I'm so happy for the team to win today.”
“It's been three months I didn't start, it's been a special day for me and all of us.”