The famous duo were surrounded by their loved ones at the Hotel Bel-Air Saturday evening as the couple celebrated their engagement.
"It was filled with close family and friends and the couple seemed really happy and in love," an insider tells E! News before noting that the future Mr. and Mrs. Spiegel were "very affectionate throughout the party."
Our source also noted that the gorgeous, floral-filled affair was equal parts "classy and chic."
"Everyone was celebrating and having a great time. Miranda and Evan get along with each other's friends perfectly."
The couple announced that they were engaged over the summer after the model posted a bitmoji showing the Snapchat CEO proposing on social media.
"I said yes!!!" the Aussie model captioned alongside a pic of her new sparkling diamond engagement ring.
Kerr and Spiegel have been dating since June 2015 but met earlier the year prior and have been nearly inseparable ever since.
This marks the second marriage for Kerr, who was previously married to Orlando Bloom, and the first for the tech entrepreneur.