... Spencer Pratt and Heidi Montag are engaged!
The 23-year-old Pratt popped the question to the 20-year-old Montag on Tuesday night at the Bacara Resort & Spa in Santa Barbara.
An Us Weekly source close to Heidi and Spencer reports they are thrilled, and adds: "She said 'yes.' She's over the moon!"
Expect staged photos of their happy engagement any second now.
An eyewitness at the store says, "She was trying on tons of them and they looked really happy!"
Heidi was formerly a close friend and roommate of The Hills star Lauren Conrad until Pratt caused a rift between the two and lured Montag away from LC's pad and into his dungeon.
The couple has not yet set a wedding date, but don't think the PR guru won't keep us well aware of it throughout the planning.