Preheat oven to 375°F (190°C) and lightly grease or line two baking sheets with parchment paper.

In a medium mixing bowl, whisk together the flour, ground ginger, ground cloves, nutmeg, allspice, salt, and baking soda.

In a saucepan over low heat, or in the microwave, melt together the butter, brown sugar, molasses, and rum.

Stir the molasses mixture into the flour mixture until well combined. The dough will be wet and sticky.

Cover the dough and refrigerate for at least 30 minutes, or longer, to allow it to firm up.

Use a large spoon or cookie scoop to portion the dough into 2-inch balls.

Place the balls onto the prepared baking sheets, leaving about 2 inches between each cookie.

Slightly flatten each cookie with your hand or the back of a spoon.

Bake in the preheated oven for 11 minutes, or until the edges are set but not dark brown.

Remove the baking sheets from the oven and transfer the cookies to a wire rack to cool completely.

Once the cookies are barely warm, store them in an airtight container.