In food processor or large bowl: Mix 1st four ingredients.
Cut in butter until resembles coarse sand. Slowly add egg yolk, lemon zest, and buttermilk until combined.
Turn out onto lightly floured, Dough EZ pastry mat to incorporate all remaining flour and gently fold in fruit or fresh berries.
Fold mat cover over dough. Use rolling pin with light pressure to roll dough to a nine inch round of 1" thickness. *Sprinkle with additional course sugar if desired.
Use bench scraper or butter knife to cut into 8 sections.
Move to parchment paper, prepared cookie sheets leaving 1-2" apart.
Preheat Oven: 400º F
Bake time: 25 minute or until golden brown
Stir together: Zest of 1 Lemon, Juice of 2 Lemons, and confectioner sugar.
Allow to cool before glazing. Allow to dry and store in an air tight container.