Preheat your oven to 350 °F (about 180 °C) and line two baking trays with parchment paper. This ensures even baking and easy cleanup later.
Sift together the flour and ground ginger into a large mixing bowl. In a small saucepan, melt the butter, treacle, and brown sugar over low heat. Once melted, remove from heat and stir in the baking soda—this will foam slightly, making the dough lighter.
Pour the warm treacle mixture into the dry ingredients and mix lightly with a spoon. Then add the beaten egg and stir until everything comes together into a soft, smooth dough. If it feels sticky, add a touch more flour until it’s easy to handle.
Transfer the dough onto a lightly floured surface and knead gently until smooth. Roll the dough out to about 1/8 inch (3 mm) thick. Use your gingerbread man cutter to cut out shapes and place them on the prepared trays. Gather the scraps, re-roll, and cut again until all the dough is used.
Bake one tray at a time for 12–15 minutes, or until the edges just start to turn golden brown. Keep an eye on them during the last minute—they can overbake quickly. Let the cookies cool on the tray for a few minutes before transferring them to a wire rack.
Once completely cool, decorate your gingerbread men with icing, chocolate, or small candies. This is where you can get creative—smiling faces, buttons, or festive designs, it’s all up to you!