Authentic Greek Green Olive Soup

The first time I made this soup was about thirty years ago.
Every time I make this it seems to taste just a little better.

Ingredients:
20 big Green olives, pitted
3 tablespoons extra-virgin Olive oil
1 Yellow onion, peeled and sliced
2 Cloves garlic, peeled and crushed
4 cups good chicken stock
1 cup heavy cream
4-6 tablespoons all purpose flour
cooked with 3 Tbsp olive oil to make roux
Black pepper to taste
Hot pepper sauce to taste
1/4 cup Dry sherry
lemon juice

Directions:
Soak the olives in cold water for 1 hour.
Drain andcoarsely chop the olives.
Heat a frying pan and add the oil, onion,
and garlic, along with 2/3 of the olives.
Saute until the onions are transparent.
Puree this mixture in a food processor
along with 1 cup of the chicken stock.
Place this mixture in a 4-quart saucepan
and add the remaining stock.
Simmer for 20 minutes and add the cream.
Whisk in the roux and simmer,
stirring constantly, until thickened.
Add pepper to taste and the remaining
chopped olives,hot pepper sauce, and dry sherry.
Heat to serving temperature and lemon juice,
serve with the sliced olive and crouton garnish.