Preheat oven to 350F. Line cookie sheets with parchment paper or silicone baking mats. Set aside.
In a large bowl, beat the butter and brown sugar until well-combined, about 2-3 minutes on medium.
Scrape down the bowl as needed as you continue.
Mix in the molasses until well-combined, about 1-2 minutes on medium.
Add the egg, and mix in until well-combined, about 1 minute on medium.
Add the flour, baking soda, and spices.
Stir in until combined. The dough will be a stiffer dough.
Scoop by tablespoonfuls and place 2 inches apart on the prepared baking sheets.
Bake for 7-10 minutes, or until the tops and edges are set.
Cool for 5 minutes on the cookie sheet.
Remove to a wire rack to cool to room temperature.
Sprinkle the tops with powdered sugar before serving.
Butter: I use salted butter in this recipe since there isn't any additional salt in the recipe. You can use unsalted if you prefer. However, you may need to add a couple pinches of salt. Also, cool room temperature butter will dent when pressed, but the butter around the dent won't lose shape. If the butter is too warm, the cookies will spread too much as they bake.
Brown sugar: I use light brown sugar, but you can use dark brown sugar if you prefer.
Molasses: I prefer to use a regular or robust unsulphured molasses (like Grandma's or Brer Rabbit). I don't recommend using blackstrap molasses in this recipe.
Flour: To properly measure the flour, I recommend weighing it. If you don't have a kitchen scale, sift or stir the flour to break it up. Lightly spoon into the measuring cup to avoid packing in the flour and level. Too much flour will give you a heavy, doughy, or crumbly cookie.
Baking: Slightly underbaking the cookies will help to keep them soft. These cookies won't spread much as they bake. There are step-by-step photos above the recipe for reference.
Powdered sugar: I just sprinkle powdered sugar over the tops of the cookies. If you prefer, you can roll the cookies in powdered sugar to coat them.