Former 'Dexter' star Julie Benz is getting married! The 39-year-old actress is engaged to long-term boyfriend, marketing executive Rich Orosco, her rep confirmed to PEOPLE on Monday.

Orosco, 38, proposed to Benz on Sunday in the backyard of the home the couple shares in Los Angeles. And the engagement ring? It's a customized Kwiat cushion-cut diamond and platinum engagement ring--complete with a diamond frame and milgrain edge band.

"It was absolutely perfect," Benz, who will next be seen in the USA hit 'Royal Pains,' told PEOPLE.

Right after the engagement, nearly 60 of their friends and family joined them for a surprise Mexican-themed engagement party, planned by Orosco.