1) combine butter & sugar - beat 2-3 min until light & fluffy
2)add egg & egg yolk & vanilla - mix on low
3)whisk flour,b. powder & salt then add to butter mixture & mix till full combined
4)divide dough in 1/2- mix cocoa into 1/2 dough
5)place each 1/2 in parchment paper & press to 1/2 onch thickness-put another piece of parchment on top & roll until about 9" square
6) chill 1/2 hour
7) remove from refrigerator & take top piece of parchment off & place dough on top of each other
8) roll dough like log make sure to make tight & get air out
9)wrap dough in saran wrap -twisting ends like bread bag tie
10)refrigerate dough at least 2 hours if need to make rounder you can take it out in 1/2 hour & gently roll on counter
11)Preheat oven - 375-line cookie trays
12)unwrap dough & slice 1/4" slices-roll edges in sprinkles or nuts
13)bake 8-10 min