The Frenchman had taken some criticism as he settled in following a summer move from Montpellier but took his scoring record to seven goals in 18 appearances in Saturday’s 5-2 triumph.
"It's nice to have marked my territory in the North London derby," he told French radio station RTL. "We needed to resume our progress up the table - especially since we recently lost points rather stupidly. It was the right time to have a great game.
Giroud faced his compatriot, Spurs goalkeeper Hugo Lloris, at the Emirates Stadium. The former Lyon man started for one of the first times this season and the Gunners star noted that his friend is struggling to deal with being largely second choice behind Brad Friedel.
"Hugo [Lloris] is a good friend," Giroud said. "He warned me that he would start the match and we greeted each other beforehand. He could not do much for the goals that we scored. It was hard for him.
"I did not expect to talk with him about his situation. It is not going well for him. It's hard and I'm trying to give him my full support. Things are like that. Everyone knows his qualities."