Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   4      large         onions -- chopped
   3      tablespoons   vegetable oil -- for sautéing
   1      28 oz can     tomato puree
   3      28 oz cans    tomatoes -- with juice
   2 1/2  cups          white vinegar
   4      tablespoons   packed dark brown sugar
   4      tablespoons   granulated sugar
   2      tablespoons   salt
   2      tablespoons   freshly cracked black pepper
   2      tablespoons   paprika
   2      tablespoons   chili powder
   4      tablespoons   molasses
   1      cup           orange juice
   2      tablespoons   liquid smoke
   8      tablespoons   brown mustard -- Dijon-style

Preparation:

In a large, heavy-bottomed saucepan, sauté the onion in the oil over medium-high heat until golden brown, about 7 to 10 minutes. Add all the remaining ingredients, bring to a boil, then reduce the heat and simmer uncovered at the lowest possible heat for 4 hours. (This long cooking removes as much acidity as possible from the tomatoes.) Puree sauce in 2, 3, or more batches to prevent it from spilling out of your food processor or blender. Will keep 2 weeks, covered, in the refrigerator.