Cover beans with water and bring to a boil. Boil for 2 minutes. Remove from heat and let soak for 1 hour. Drain. Add beans back to the stockpot and add the water, whole garlic, onion, cayenne, vinegar, and salt. Place over medium heat and simmer for 30 minutes. While beans are simmering, combine in a skillet and saute, olive oil, garlic and sausage. Stir in tomatoes, oregano, sherry, squash and green onions. Deglaze skillet with one cup of stock. then transfer mixture to beans. Add remainder of the stock, stir to blend and reduce heat to low. Cook for 30 minutes. The broth should be thick. Serve.