For the cookies: In a stand mixer fitted with the paddle attachment, beat the butter until it is airy and creamy, about 3 minutes. Add the brown sugar and molasses and beat for 1 minute. Scrape down the sides with a rubber spatula. Beat in the egg. Add the almond extract and orange zest and beat to combine.
Add the flour, ginger, cinnamon, baking soda and salt and turn the mixer on low. Allow to mix until the mixture comes together, about 1 minute.
Form the mixture into 2 separate discs about 1-inch thick. Wrap each disc in plastic and store flat in the fridge for about 4 hours or up to overnight.
When ready to bake, preheat the oven to 350 degrees F. Spray 2 baking sheets with nonstick spray.
Roll out each disc between 2 sheets of parchment paper to about 1/4-inch thick. Cut each into shapes and place on the prepared baking sheets.
Bake the cookies, rotating the baking sheets and switching their positions halfway through, until the centers are barely set, 9 to 11 minutes. Let cool completely on the baking sheets on a rack.
For the icing: Combine the powdered sugar and butter in a bowl and stir together with the lemon juice and half the milk. Add more milk as needed to achieve a pipeable consistency. Tint with food colorings as desired. Transfer to piping bags.
Decorate each cookie as desired. Let set completely, about 30 minutes.