Spicy Tomato Ketchup

28 oz can stewed tomatoes
1 small yellow or red onion, diced
1/2 teaspoon ground cinnamon
1/4 teaspoon celery seeds
1/4 teaspoon ground mace
1/4 teaspoon ground cloves
1/4 teaspoon ground allspice
1/4 to 1/2 teaspoon cayenne pepper, to taste
1/4 teaspoon salt
1 1/2 teaspoon brown sugar or hone, or to taste
2 tablespoons balsamic vinegar
apple cider vinegar to taste

Stew tomatoes with onions, uncovered, for 40 minutes until they are well broken down, or simmer stewed tomatoes with onions until onions are soft
Puree tomatoes and onions
Return to pot and add cinnamon, celery seed, mace, cloves, allspice and cayenne, simmer over medium heat until thick, stirring frequently
When sauce reaches desired consistency (40 minutes to an hour), add salt, sugar or honey and balsamic vinegar
Add cider vinegar and adjust other seasonings to taste

Serve with patatas bravas