Sift together7 ½ oz all-purpose flour, ⅛ teaspoon table salt, ⅛ teaspoon baking soda and 1 teaspoon ground cinnamon. Set aside
Cream 6 oz unsalted butter and 6 oz confectioners' sugar until the mixture lightens in color and is aerated, about 2 minutes. Scrape the bowl thoroughly. Add 2 oz pistachios (finely ground), ½ teaspoon vanilla extract and 1 tablespoon dark rum. Add 2 large egg yolks and mix just until combined. Scrape the bowl thoroughly. With the mixer running on low speed, slowly add the flour mixture.
Turn the dough out onto a lightly floured surface and knead lightly to finish combining the ingredients. Split the dough into two equal portions and form each into a disc. Wrap and refrigerate for several hours until chilled and firm.
Preheat the oven to 350 °F. Line two ½sheet pans with parchment paper.
Remove one of the dough discs from the refrigerator. Knead the dough briefly to soften just a bit. Roll the dough to ⅛" thick and use a cookie cutter (whatever shape you prefer) to cut out cookie bottoms.
Set the cookie bottoms onto one of the prepared sheet pans, spaced ¼" apart.
Reroll the scraps and continue cutting until the first portion of dough is gone. If the dough gets too soft to roll return it to the refrigerator to firm up.
Roll the second portion of dough to ⅛" thick and use the same cutter to cut cookie tops. Use a smaller cutter to cut a hole in the center of each cookie top. Continue rolling and cutting until you have an equal number of cookie tops and bottoms.
Bake until lightly golden around the edges, about 7-8 minutes. Turn the trays after 5 minutes through the baking time. Cool completely.
While the cookies are cooling, warm 16 oz apricot preserves briefly in the microwave then strain to remove chunks of fruit.
Dust an even layer of confectioner's sugar over the cooled cookie tops. Flip the cookie bottoms over so the flat side is facing up. Spread a thin layer of apricot preserves over each cookie bottom.
Carefully place a cookie top onto each cookie bottom to form a sandwich. Use a pastry bag or small spoon to fill the cut-outs with the strained apricot preserves. The is easiest of the preserves are still a little warm.