Preheat oven to 375°F. Line cookie sheets with parchment paper or silicone baking mats.

Place flour and salt in a medium bowl. Use a pastry cutter to cut in butter until pieces are pea sized. Drizzle 1 tablespoon half and half over part of the flour mixture. Gently toss with a fork and push to side of the bowl. Repeat with remaining half and half, 1 tablespoon at a time, until mixture is moistened and dough comes together. Form dough into a ball.

Roll out dough on a lightly floured surface. Roll until the dough is just less than 1/8 inch thick. Use a 1 ½ to 1 ¾ inch cookie cutter to cut rounds. Place 1 inch apart on cookie sheet.

Bake until light golden around the edges, about 8-10 minutes. Cool before filling.

Make the filling by whisking powdered sugar and salt. Stir in softened butter and vanilla until smooth then add enough half and half to make the frosting spreadable. You can tint the filling, if desired.

Spread frosting on the bottom of each cookie and sandwich with a second cookie.