Turkish Shortbread

400 gr butter/margarine, at room temperature
9-10 Tbsp powdered sugar
1 Tbsp vanilla
3 cups corn starch
2 cups all purpose flour,
½ cup powdered sugar for top (optional)

Take powdered sugar and soft butter/margarine in a large bowl. Knead until it gets homogeneous. Add starch slowly, while kneading. Also, add vanilla as well. Then, add flour slowly. Knead until the dough becomes smooth and soft. If you use excess flour, it will be difficult the give stable shapes. So, you do not need to use all the flour mentioned, if you think the dough is already soft and smooth (I used 2 cups of flour, though).
Grab large pieces of dough and on a flat surface roll it with your hands to make a long stick, thick as your thumb. Using a knife cut 1 inch pieces diagonally. Make stripes with the back of a fork on each piece pressing gently on the surface. Use the same procedure for the remaining dough. Place them over a greased oven tray leaving room between.
Bake in a preheated 325F (160 C) oven for about 20-30 minutes or until their bottoms get pinkish. Make sure the tops remain white. Make sure they do not turn pinkish.
Let them cool for a while and if you desire sprinkle with powdered sugar on tops with a strainer.
ENJOY