Credit: National Photo Group

Mazel tov, you guys! Lauren Conrad and William Tell got engaged over the weekend, and the newly betrothed pair celebrated by . . . hitting the supermarket? The Hills alum, 27, and the rocker-turned-USC law student, 33, hit Pavilions in West Hollywood on Sunday, Oct. 13, where they picked up cases of wine, beer and apple cider, among other items. Conrad announced her engagement via Twitter that same day, and was happy to flash her sizable engagement ring from her man during the trip, where they seemed to be stocking up for a big party.

The bestselling author and designer was super-casual -- yet stylish, of course -- for the errand, wearing a loose beige cardigan over a white blouse with cutoffs, ballet flats and sunglasses, her hair up in a bun.

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She and Tell -- grizzled with a deep v-neck t-shirt, shorts and flip-flops chatted as he pushed a full grocery cart out to their car. Conrad (whose exes include Kyle Howard and Hills/Laguna Beach alum Stephen Colletti and Brody Jenner) began dating on Valentine's Day 2012, and recently moved in together in her condo in L.A.'s Brentwood nabe.

To her fans' delight, Conrad promised to share the wedding lead-up every step of the way. "I am beyond thrilled! Get ready for lots more wedding content here on as we begin the planning process," the mini-mogul said as she announced the engagement.