Bring Lentils, Stock, Celery, Bay Leaf And Oregano To A Boil. Cover And Simmer For 30 Minutes. Remove And Discard Bay Leaf. In A Frying Pan, Saute Onions And Garlic In Oil For 5 Minutes. Add Salt, Pepper, Parsley And Tomatoes. Simmer For 5 Minutes. Add Onion Mixture To The Lentils. Simmer For 5 Minutes. Add Greens And Simmer For 10 Minutes. Add Vinegar And Tabasco And Serve.