The best compliment. Reese Witherspoon couldn’t contain her joy when a fan thought she was Carrie Underwood. “To the woman in the parking lot who just asked me if I was Carrie Underwood: You officially made my day!” Reese, 44, gushed on Twitter on Sunday, June 28, which prompted Carrie, 37, to respond.

“YOUR day?!?!?!?! That lady just made my whole life!” the “Before He Cheats” singer hilariously said.

After the fan saw Carrie and Reese’s exchange, she took to Twitter to reveal why she thought the Big Little Lies actress was someone else. “OK, so [the] craziest thing just happened. I’m with my husband eating at a BBQ place and I swear I see a lady with her husband and kid. I’m like, that looks just like a celebrity and I’m trying to think who … and I’m like, ‘Who? Carrie Underwood?'”

Even though Reese was wearing a face mask and a cowboy hat, the fan was sure that it was the American Idol alum so she waited for her idol to get back to her car before she asked any questions. “[Reese] goes, ‘Hey, no I’m not Carrie Underwood but have a great day.'”

It wasn’t until Carrie’s follower went back to the restaurant that she realized it was the Cruel Intentions actress. “Now I feel crazy and I want to go back and be like, ‘I’m so sorry. I love you from Legally Blonde, but I don’t know what I was thinking,'” she laughed.

The fan captioned her Twitter post, “OMGGGG! That was ME. Haha, I swear when I walked away I was like wait, that was totally Reese Witherspoon! I could [barely] see your face cause the mask and hat but I knew you looked so familiar haha. I LOVE YOU @ReeseW.” What a great story to tell at dinner parties.

Reese and Carrie are really good friends. The Oscar winner took her 20-year-old daughter, Ava, to her pal’s concert once and Carrie said she would love to have Reese play in her movie during a previous interview with Taste of Country. “I’ve always loved Reese Witherspoon and I feel like we have the same stature,” the musician gushed. “We’re about the same height and she can sing.”