With no electricity for the fourth straight day Tuesday, chef and caterer Jane Sykes realized she would have to throw out $1,000 worth of food, including trays of brownies, cupcakes and puff pastry. “I don’t think PG&E really thought this through,” she lamented. Frustration and anger mounted across Northern California on Tuesday as the state’s biggest utility, Pacific Gas & Electric, began another round of widespread blackouts aimed at preventing its electrical equipment from sparking wildfires in high winds.