Just as we turn back the clocks to regain the hour we surrendered last spring, winter arrives in Napa Valley. That means rain, and very chilly, sometimes frosty, nights. The grapevines are starting to shed their yellowing leaves in preparation for dormancy and eventual pruning. The heirloom tomato plants, exhausted, have been pulled from the garden. We enjoyed our first comfort-food dinner in months: Spicy sausage, white bean and escarole stew (see "Enjoy" page for the recipe).