Chilled Artichoke Citrus Soup

 2 Tblsp olive oil
 1 cup chopped onion
 1 cup chopped leek, tender white part only
 1 garlic clove, minced
 2 tsp chopped fresh thyme
 3 (13.75 oz.) cans artichoke bottoms, chopped
 1 lemon, thinly sliced and seeds removed
 7-8 cups chicken stock
 1 cup heavy cream

In a large sauté pan, warm the olive oil over medium heat. Add the onion and sauté for 1 minute. Add the leek, garlic and thyme and continue to sauté until translucent. Add the artichoke bottoms and lemon and sauté for 2 minutes. Then add 7 cups of the stock, bring to a boil then simmer for 40 to 45 minutes or until the artichoke bottoms are very tender.
Allow to cool. Remove the lemons, then puree in batches in the blender. Return to sauté pan over very low heat and add the last cup of stock if mixture is very thick. Add the cream. Season with salt and pepper and chill overnight.