How to Make It
Combine onion and vinegar in a large bowl; toss well.
Heat oil in a large Dutch oven over medium-high heat. Add onion mixture. Cook 5 minutes; stir occasionally. Stir in wine and remaining ingredients; bring to a boil. Reduce heat. Simmer until liquid almost evaporates; stir occasionally (about 1 1/2 hours). Increase heat to high. Cook 3 minutes; stir constantly.
Note: Most of the alcohol evaporates when heated, but a nonalcoholice red wine can be substituted.