1½ cups leftover mashed potatoes (it's better if you use plain mashed potatoes, but I've had success with leftover mash that has butter and milk added)
1 egg, beaten
⅓ cup cold water
⅓ cup milk
1 tbsp milk for brushing the tops
Instructions
Preheat the oven to 450F
Sift together the flour, baking powder, salt, pepper and sugar
Cut in butter with pastry cutter, two knives, or your fingers, until butter is well incorporated
You can add a handful of grated cheese, or chives, as I did, but that is optional
Add mashed potatoes and stir with fork until no large chunks of mashed potato remain
Add egg, water and milk, stirring until a loose dough forms
Knead dough 6 to 8 times on a floured counter until the dough holds together
Press dough out to ¾ inch thickness and cut into circles with a cookie cutter or glass
Put biscuits on an ungreased baking sheet
Brush the tops lightly with milk
Bake 15 to 20 minutes or until golden
Eat immediately with giant swodges of butter
Recipe by You Have Been Served at https://www.youhavebeenserved.ca/2015/12/10/mashed-potato-biscuits-recipe/