Brown the butter in a medium saucepan at medium heat. Once the butter starts to foam and you can see them start to turn a light brown, stir continuously until the butter is fully browned about 5-7 minutes.
Add the melted browned butter to a bowl and freeze it for 15-20 minutes until it has thoroughly cooled.
Preheat the oven to 350°F degrees.
In a large mixing bowl, combine the cooled browned butter and brown sugar.
Add the egg and molasses and combine.
Add the flour, salt, baking soda, cinnamon, ginger, allspice, and nutmeg to combine.
Use a ¼ cup measuring cup to measure out ¼ cup worth of dough for each cookie. Place 6-8 cookies on a baking sheet.
Bake at 350°F for 10-12 minutes.
Sprinkle the cookies with turbinado sugar immediately after taking them out of the oven. Allow the cookies to cool.
Notes
Cinnamon: In general, I prefer using a high-quality Ceylon Cinnamon. In recipes that feature cinnamon. It makes a big difference to use a high-quality version. I like using the brand Simply Organic.
Browning Butter: If you're concerned about burning the butter (which can happen quickly after it browns, keep the heat slightly lower (a #3 or #4 out of 10 on an electric stove). It will take longer to brown the butter, but you'll be less likely to burn.
Turbinado Sugar: Sprinkling the cookies with sugar after baking them allows you to cover more surface area as the cookies spread out when they are baked. If you add the sugar while they are still warm out of the oven, the sugar will stick to the cookies.
Turbinado sugar is a brown sugar with larger sugar granules and can be found at many grocery stores in the baking aisle. Adding it is optional but adds a festive touch and a slight sweet crunch.