Beat the softened unsalted butter and packed brown sugar together until smooth, then add the egg, molasses, and vanilla and beat again until evenly combined. The mixture should look glossy and cohesive, with no streaks of butter.

Fold in the all-purpose flour mixture of baking soda, cinnamon, ginger, cloves, allspice, black pepper, and salt until a thick dough forms. Stop mixing as soon as no dry flour is visible, and the dough should be uniform and dark brown.

Scoop the dough into 2-tablespoon ovals and arrange them on a sheet pan with space between. The cookies should be similar in size so they bake evenly.

Bake at 350F for 10–12 minutes, until the edges look set and the centers still look slightly soft. A light spring-back when touched is the visual cue.

Cool the cookies completely on the sheet pan before filling. This prevents the vanilla cream from melting or sliding.

Beat the softened unsalted butter and softened cream cheese until smooth, then beat in the marshmallow creme. Continue until the mixture looks thick and very smooth.

Gradually beat in the powdered sugar, then add vanilla and cinnamon and beat until very fluffy. The filling should hold shape when you lift the beaters.

Match the cookies in pairs by size, then spread the filling generously on one cookie and press together with the other. Use a slightly domed filling layer so the sandwich resembles a “cream pie” filling.