My mom made these every year when I was growing up, the memories of her baking all those years are so cherished, she passed away in January this year. I have been making these as part of my holiday baking every year since I left home/married/started my family. My kids are now grown and I have passed on the recipe to my only daughter (I also have 4 boys), who is engaged and she plans to carry on this tradition with her family as it grows. This is a cookie that is so simple and flavorful...and elegant on the cookie tray. It is most asked-for recipe each time someone new gets a 'cookie box' from me during the Christmas holiday season...and there are 15-20 different cookies in each box!
Mix the water with the separated egg white in a cup until frothy, set aside
Beat butter and sugar together with a mixer until combined, add the separated egg yolk and cinnamon and beat until creamy.
Slowly, add the flour and mix until combined, do not overmix.
Press this into a cookie sheet with at least a 1/2" side all around (no air bake pans, or cookie sheets with no sides). Working gently with your fingers, press the dough to cover the entire cookie sheet. This should cover the sheet being 1/16-1/8" thick. Thinner is better.
Brush the egg white mixture gently over the top and sprinkle on the walnuts. Bake at 350 degrees for 20-25 minutes, until very LIGHTLY browned.
Cool, then cut into desired shapes, I have done 2" squares or diamonds...depends on the event and your mood. Serve with coffee, tea or include in your holiday baking extraveganza (cookie box, or care package for my kids living far away)...they are wonderful!