Beat the butter and brown sugar until fluffy, about 2 minutes. Mix in the molasses, egg, and vanilla. Whisk the flour, spices, baking soda, and salt. Add the dry ingredients to the wet in two additions, mixing just until combined. Cover and chill the dough for at least 1 hour.

Preheat the oven to 350°F (175°C) and line baking sheets with parchment. Roll the chilled dough 1/4 inch thick on a floured surface. Cut 2-inch rounds and transfer to the sheets an inch apart.

Bake for 8 to 10 minutes, until edges are set and tops look dry. Cool on the sheet for 2 minutes, then move to a wire rack to cool completely.

Beat the cream cheese and butter until smooth. Add the sifted powdered sugar, vanilla, and salt. Whip until light and spreadable, about 1 minute.

Spread or pipe about 1 tbsp of filling onto the flat side of one cookie. Press a second cookie gently on top. Serve once the filling sets slightly.