Mix Dry Ingredients: In a bowl, whisk together the flour, spices, baking soda, and salt.
Cream Butter & Sugar: In a separate bowl, beat butter and brown sugar until light and fluffy. Add molasses, egg, and vanilla; mix until smooth.
Combine: Gradually mix the dry ingredients into the wet ingredients until a dough forms. Chill the dough for at least 1 hour.
Preheat & Shape: Preheat oven to 350°F (175°C). Roll out the dough (1/4 inch thick), and use gingerbread man cookie cutters to shape.
Bake: Bake on lined sheets for 12-15 minutes until firm around the edges. Cool on a wire rack.
Decorate: Once cooled, decorate with royal icing or buttercream and optional sprinkles.