In a saucepan combine chicken stock, onion, and vegetable of choice. Bring mixture to a boil, reduce heat and cover and simmer until the vegetables are tender. Place half the vegetable mixture into a blender and blend until smooth. Pour into a bowl. Repeat with remaining vegetable mixture. Set aside. In the same saucepan, melt the butter. Blend in flour, salt, pepper. Add milk all at once. Cook ad stir till mixture is thick and bubbly. Stir in the blended vegetables. Cook and stir till soup is heated through. Season to taste with salt and pepper. Season soup with your choice of thyme, garlic powder, basil, parsley, nutmeg, sage, curry powder. Garnish with croutons and bacon.