Villa won 2-1 as Buendia and Jhon Duran from the penalty spot saw off Wycombe, which struck in injury time through Richard Kone.
It was Buendia's first start after missing the entire last season due to knee injury.
"It was a really special night, obviously to come back and play again for this club," Buendia told Sky Sports after full-time. "It is my fourth season here and I really love this football club, so to help the team with a goal, it is an amazing feeling.
"It was where I need to be more often to get into the box. The defection came to me and I tried to head it over the goalkeeper."
Buendia added: “We have a really big squad, which is what she showed today. We have an amazing academy too, so today we showed quality. We knew that coming here would be really hard.
"They pressed hard and pushed us a lot. We tried to play our game and keep going in our philosophy and we got our win."