First half goals from Bernardo Silva and Sergio Aguero moved Guardiola's side one point clear of previous leaders Liverpool.
It was a confident display from City in the west London sunshine and Guardiola was impressed with the rhythm his team showed after the two-week international break.
"Our first 15-20 minutes was one of the best of the season. We played with incredible spirit, we could have scored more. After the goals we controlled it," he said.
"It was an incredible result after the international break and having played away. We did what we should do.
"After the break playing at home is different to playing away. Always you have doubts about how they're going to react.
"Fulham was a tough game for Liverpool and Chelsea so we knew it was going to be tricky, 12:30 on Saturday, a sunny day.
"That is unusual and that is why I am so satisfied."
Although Liverpool would regain pole position if they beat Tottenham at Anfield on Sunday, City have a game in hand and will be crowned champions for the second successive season if they win their last seven matches.
Guardiola isn't thinking that far ahead just yet and he urged his players to take it one game at a time.
"Liverpool and Man City have done incredible so far so deserve the credit. We will have 80 points with six games to play if we win next week," he said.
"We are going to do everything to win. No matter the next competition, we will win the game."
City, who have already won the League Cup, remain in contention for an unprecedented quadruple as they chase Premier League, Champions League and FA Cup glory.
But Guardiola said: "We don't think too much about what people say about the quadruple. Enjoy the moment and dream to win another game."