In a large stock pot, heat oil and sauté onion until golden. Remove onions.
Add flanken, broth, and water. Bring to a boil, skim froth.
Add sauteed onions, cabbage, tomatoes, lemon juice, carrots, paprika, bay leaf, salt, pepper. Stir on medium heat.
Taste and slowly add amount of sugar to taste.
Simmer for 1 ½ - 2 hours. When meat is fork tender, remove from heat.