Preheat oven to 350F. Line cookie sheets with parchment paper or silicone baking mats. Set aside.
In a large bowl, beat the butter and sugars together on medium until fluffy, about 3 minutes.
Add eggs, vanilla, and molasses.
Mix until well-combined, about 1-2 minutes on medium.
Add the flour, baking soda, salt, ginger, cinnamon, and allspice.
Stir in just until combined. Don't overmix.
Scoop 1.5 tablespoon scoops (medium cookie scoop) of dough.
Dip the tops in the sparkling sugar.
Place the scoops of dough with the sugar side up on the prepared baking mats.
Bake for 8-14 minutes. The edges should be set but the cookies should look slightly underbaked in the cracks.
Let cool on the baking sheets for 5 minutes.
Transfer to a wire cooling rack to cool to room temperature.
Butter: I use salted butter in this recipe. You can use unsalted if you prefer. 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 or doughy cookie that doesn't spread.
Baking: Slightly underbaking the cookies will help to keep them soft and chewy. The cookies will look set at the edges and on top but should look slightly underdone in the cracks.