Beat butter for 30 seconds. Add sugar and beat well until fluffy.
Add vanilla and water and beat well until combined.
Stir in flour and chopped pecans until fully incorporated.
Roll balls of dough into finger shapes, about 2 inches long. Curve slightly and place on ungreased baking sheet. Cookies don't need to be spaced too far apart as they don't expand much during baking.
Bake in centre of 325° oven for 20 minutes until bottoms are slightly golden brown.
Cool on a rack at least 5 minutes.
Place rack over baking sheet. Dust cooled cookies with powdered sugar. For best results, use a mesh strainer and tap gently with one hand while moving the strainer evenly over all the cookies.