This a great recipe to use up your bumper crop of cucumbers. The original recipe appeared in Eliza Acton's Modern Cookery for Private Families, a best selling book in the 19th century, and now has a new life featured in the new Official Downton Abbey Cookbook. Bonus is that this a keto friendly recipe.
Add the cucumbers, shallot, salt, and cayenne pepper in a large saucepan, and bring to a boil over high heat.
Reduce to simmer, partially cover and cook until the cucumbers are tender, about 45 minutes
Use a hand blender to purée until smooth. Alternatively use a blender and process in batches. Return to the saucepan and heat on medium.
Add the rice flour to the cream to dissolve it and then sitr the cream mixture into the soup. Keep stirring for another 10 minutes on a gentle simmer, until the soup has thickened.
Mince the parsley before serving and stir in. Ladle the soup hot. You can also serve this soup cold.