1 Tbs. olive oil
1 medium onion, finely chopped
 (28-oz.) can organic tomato puree
1 Tbs. tomato paste
½ c. cider vinegar
¼ c. packed dark brown sugar or sugar in the raw
¾ tsp. salt


Heat the oil in a medium saucepan over medium-high heat. Add the onion and cook, stirring occasionally, until the onion is tender, about 8 minutes. Add the remaining ingredients; bring to a boil. Reduce the heat and simmer, uncovered, stirring often to prevent scorching, until the ketchup is thickened and the flavors are blended, about 1 hour.