Lauren Conrad and William Tell have been happily dating since Valentine's Day, but it wasn't until October 5 that the couple made their first joint public appearance at the Third Annual Veuve Clicquot Polo Classic in L.A.'s Pacific Palisades.

A stunning Conrad, who wore a self-designed Paper Crown dress, posed solo on the red carpet. She joined the University of Southern California law student, 32, inside the event, held at Will Rogers State Historic Park.

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Tell was dressed to impress in navy slacks, a blue button-down and a polka dot bow-tie. "He dresses himself," a proud Conrad told Us Weekly.

The pair, who both hail from Orange County, "are very serious," a Conrad pal told Us in September. Another friend said Tell is different from the bad boys, like Jason Wahler and Doug Reinhardt, whom Conrad dated on The Hills. "He worships her."

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Conrad, who fronts the Paper Crown and LC Lauren Conrad fashion lines, will release two new books October 16: the novel Starstruck and the lifestyle guide Lauren Conrad Beauty. Though she's about to embark on a nationwide promo tour, the ex-MTV reality star still finds time to pamper her man.

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"For dinner, I make stuffed peppers," Conrad told Us. "Twelve at a time, and then I put them in the freezer!"

This article originally appeared on Lauren Conrad and William Tell Attend First Public Event Together!