French Butter Cookies - Sables

1 cooked egg yolk
1 1/4 stick butter
1/3 cup + 1 tbl sugar
1/4 tsp salt
1 tsp vanilla
1 1/2 cups flour

glaze
1 egg white
1 tsp water
4 tsp turbinado sugar

cover egg 1" water
bring to boil high heat - remove from heat cover and let stand for 10 mins
plung in ice water bath and let set for 5 minutes
remove yolk from egg and press through fine mesh strainer
using paddle cream egg, butter, sugar and salt, mix on medium until light and fluffy about 4 minutes, scrap sides
add vanilla and mix until incorporated
stop mixer and add flour
mix on low speed just until combined - about 30 seconds
use a rubber spachela to press dough into a round
divide dough in half, wrap each half in 12" square sheet of parchment paper, shaping as a log 6" long and 1 3/4" diameter, twist ends to compact dough
chill logs for 1 hour or until firm
unwrap logs and trim ends
mark dough 1/4" slices
cut rounds rotating dough a quarter turn so not to deform log

place cookies 1" apart on parchment lined cookie sheet
brush with mixture of egg white and water and sprinkle evenly with sugar

bake at 350 until the centers are a pale golden brown and the edge are slightly darker, about 15 minutes
cool on sheets for 5 minutes then transfer to wire rack to complete cooling.