The One Direction heartthrob ordered the sweet treats from Chapelford Village's Custom Cupcake Company in Cheshire, northwest England to help his girlfriend celebrate her big day.
Co-owner Matt Blakely told E! News: “A lady called us asking if we could supply some cupcakes. I told her we were busting at the seams because of the holidays. She said it was for Harry Styles, and I said, 'Oh, OK, cool. Send him along.'
"Later, I got a phone call from my wife that Harry Styles was standing on the doorstep. I didn't think he would come to pick them up."
The couple also took a romantic drive around the English countryside before enjoying an afternoon meal in the George & Dragon Pub in the village of Great Budworth.
Earlier this week, Taylor and Harry, 18, enjoyed a romantic mini break with his parents in England's picturesque Lake District and a day out in Bowness-on-Windermere in Cumbria, where they shopped for Christmas presents together for their families.
Local eyewitness Claire Dibbs said: "I was hyperventilating, I just never expected to see them. She introduced herself, she was really lovely. She said they were just here for the day and I think they were there with his parents. Taylor said they were leaving soon.
"Taylor had a lot of bags from Beatrix Potter world - I saw some cuddly toys poking out of the top of the bag. They'd done a lot of shopping. Taylor said she loved the area and said it was really pretty."