Early goals from Oscar and Lampard, who had already had a penalty saved, offered the Blues full reward for a blistering opening that left their newly-promoted visitors chasing shadows.
And while Hull goalkeeper Allan McGregor made a couple of good saves, including a stop at the end of the first-half that the Goal Decision System proved did not cross the line, Chelsea never hit the heights of their early play.
"It was very sharp from the start. In the first half we moved the ball quickly," Lampard told Sky Sports 1.
"If we play like that we'll give most teams a game."
Asked if they slowed after half-time, Lampard added: "Maybe a little bit but it is early season and we've done a lot of travelling. I'm not making excuses.
"We were so bright in that first half that there is bound to be a come down in the second. We'll take the positives of the first half."
Lampard enjoyed the reception for Mourinho, who blew kisses to the home fans as they chanted his name before kick-off.
"It was brilliant. The crowd loved it and he loved it too," he said.
"It was a great atmosphere and it's like he has come home. We have to kick on now."
Kevin de Bruyne earned the man-of-the-match award on his Chelsea debut, setting up Oscar for the opener.
"It was a good start especially in the first half," he said.
"We began well at the start and it was nice to score two good goals.
"The second half was a little worse but it was a mature game from us."
Hull boss Steve Bruce admitted his side had been able to do little about Chelsea's dominance during their decisive opening to the match.
"The first 25 to 30 minutes it was unstoppable," he said.
"When they play with the fluidity that they did; they were a constant threat. We had to dig in big style.
"The second half it is human nature to take the foot off the gas.
"Today we had a rampant Chelsea and in the first half we simply weren't good against them, there's no shame in that."
Mourinho described his side's first half as "brilliant" as his creative players ran riot.
"It is three points and no doubt a deserved victory," he said.
"It was a brilliant first half. High intensity, high quality.
"The second half was not the same as the first but that is not a surprise because our pre-season has not been an easy one. It was a very good level.
"The game was always under control."
Mourinho thanked the fans for their support on his return, but called on them to now turn their focus to cheering on the players.
"It is something we don't forget. I made the right move by coming back; I am one of them and I am so pleased and happy," he said.
"I need my team to be supported and I need the fans to sing the players' names.
"Enough with Mourinho now and come on Chelsea.
"It's enough, I know they love me.
"Now it is my time to work for them and work for the team."