Cook 3-4 large onions with tomatoes before juicing. Let juice stand overnight and take off the clear liquid on top. Blend pulp in blender until smooth, a small amount at a time. Cook until reduced by half. Stir often.
Add the following: 1/2 tsp. dry mustard 4 tsp. salt 1/2 tsp. cloves 1 1/2 c. sugar 1 1/2 tsp. cinnamon 1/2 tsp. allspice 1/2 tsp. red pepper
Cook another 30 minutes or so until quite thick. Make a paste of cornstarch or clear jell and water. Add to catsup until desired consistency. More spice may be added to your taste. Do not use an aluminum pan.