Roughly chop the chanterelles into ½-inch pieces. Chop the shallot and thyme Melt the butter in a big cast iron stock pot and sauté the chopped shallot until translucent. Add the chopped thyme and chanterelles and sauté for additional 5 minutes. Sprinkle flour over the mushrooms and mix well. Pour the stock into the pot stirring constantly – you may use less stock for a thicker soup if desired. Bring to boil and season with salt and pepper to taste. Let the soup simmer for 15-20 minutes without the lid, let reduce uncovered for longer for stronger taste. Allow the soup to cool then mix with an electric blender until smooth. Pour the blended soup back into the pot and add sherry and heavy cream and simmer for 5 -10 minutes Taste and add salt and pepper if necessary, pour in soup bowls and garnish with thyme