Using either a (Food Processor, stand up mixer or by hand) add the flour and salt to the bowl, make a well in the flour and add the eggs, lightly mix (pulse, with a fork or beat just to wet the flour), add the sugar and mix, then add the chopped butter and mix to form a smooth compact dough, wrap in plastic and refrigerate for an hour.
Remove from the fridge and knead a few times to soften up the dough. Using a small round cutter (1.5 inches / 4 cm) or glass form cookies slightly thicker than pie dough (1/8 inch see photo). Leave half the cutouts whole and the other half cut out a small form in the middle (heart, round shape, star etc*).
Pre-heat oven to 350 degrees (180 degrees celsius). Line 2-3 cookie sheets with parchment paper.
Place cut out circles on a parchment paper lined cookie sheets and refrigerate approximately 15 minutes while oven is heating.
Bake for approximately 10-15 minutes or until very lightly golden. Let cool completely , dust the cut out cookie with icing sugar if desired. Place filling (1 teaspoon more or less of desired filling) on whole cookie and cover with the cut out cookie. Serve. Enjoy!
*Be sure to bake the small cut out forms on a separate cookie sheet because they only take about 5-6 minutes to bake.