Combine lentils, vegetable stock, and salt in soup kettle. Simmer, covered, until Lentils are soft. (about 1 hour)

Meanwhile, melt butter, then add garlic, onion, celery, and carrots. Cook until just soft.

To the lentils, add garlic, onions, celery, carrots, tomato, red wine, lemon juice, brown sugar, and red wine vinegar.
Let simmer about 15 minutes. Add salt and pepper to taste.