Begin by blooming your gelatin in a small bowl of cold water. In a saucepan, combine 1 cup of warm espresso with 1/2 cup of brown sugar, stirring until dissolved. Add in 1 cup of white chocolate, cinnamon, cloves, and nutmeg. Stir until smooth, then remove from heat and allow to cool slightly.

In a mixing bowl, combine 1 cup of mascarpone and 1 cup of heavy cream. Beat until soft peaks form, about 2-3 minutes. Fold the cooled mousse base into the whipped cream mixture until smooth and fluffy.

In a separate bowl, whisk together flour, ground ginger, and a pinch of salt. Add 1/2 cup of molasses and 1 egg yolk, stirring until a soft dough forms. Roll out to 1/4-inch thick and cut out circles for the cookie base.

Prepare silicone dome molds by greasing them. Fill with the mousse mixture, leaving space at the top. Press the cookie rounds into the mousse until just submerged. Cover with plastic wrap and freeze overnight.

Once frozen solid, heat the glazing ingredients until warm (about 90°F). Remove mousse domes from molds and place on a wire rack over a baking sheet. Pour the warm glaze evenly over the domes.

Transfer the glazed domes onto an elegant serving plate. Decorate with cocoa powder or mini gingerbread cookies if desired.