It’s an early Sunday morning in Temecula, California. The sun is high enough now to burn away the low-hanging mist that slides in from the ocean to reveal a Tuscan-like landscape of softly rolling hills, castlelike wineries and expansive ranches famous for breeding and training championship quarter- and cutting horses. Mark Matson (who looks like he could have stepped right out of a John Ford western) and his skilled horsewoman wife, Marika, are the owners of the Temecula Carriage Co. Along with their assistant, Arlene Eyerman, they’ve been up for a while, making sure the horses are fed, tack is polished and their fleet of carriages is ready for today’s champagne clip-clop tours. Ten or so miles away in the downtown section of Temecula known as Old Town, the cooking and serving staff at E.A.T Marketplace, led by Executive Chef Leah Di Bernardo, is busy frothing lattes, bagging freshly baked …