The 50-year-old singer took to her Instagram Story on Thursday to show off how she celebrated the milestone occasion.
In the posts, Stefani shared pics and videos of her boyfriend, Blake Shelton's, extravagant gift, a giant bouquet filled with pink and white flowers.
Stefani also posted clips of herself receiving multiple cakes and pies, even joking that they'd negatively impact her Las Vegas residency. "Tooooooooo much pie I'm gonna be fat in Vegas sorry," she quipped.
Throughout her special day, Stefani appeared to be surrounded by friends and family at a bash, which featured photos of her throughout the years with her gathered guests.
Her family was also there to show their love with Stefani's youngest son, 5-year-old Apollo, saying in one video, "It's Mama's birthday!," before instructing his mom to "read the card first" before opening her gift. Stefani shares Apollo -- along with his older brothers Zuma, 11, and Kingston, 13 -- with her ex-husband, Gavin Rossdale.
On Thursday, a source told ET that Shelton had big plans for his girlfriend -- whom he said he loves "so much it's actually stupid" -- in order to "make her feel special."
"He's planning a big party for her, he is going all out! It's a costume party. Gwen is a huge costume lover. She has always loved dressing up for Halloween," the source shared. "... Blake and Gwen have a lot to celebrate. They are both so incredibly happy in their relationship and in their lives right now. They have full, open communication and truly appreciate one another. Gwen is always saying she has found her soulmate and best friend."
As for how Stefani herself was feeling about her birthday this year, the source said "she's over the moon about it," adding that she "feels confident in her age and she is completely in love."