Ingredients

• 2¼ cups all-purpose flour
• 2 tsp baking soda
• 1 tsp salt
• 1 tbsp ground ginger
• 1 tsp ground cinnamon
• 1 cup butter, at room temperature
• ½ cup brown sugar
• ½ cup granulated sugar
• 1 egg ¼ cup molasses

Instructions

1. Sift together the flour, baking soda, salt, ginger, and cinnamon in a medium bowl.
2. In a large bowl, using an electric mixer or beating by hand with a wooden spoon, cream the butter with both sugars. Add the egg and beat until smooth. Beat in the molasses. Add the flour mixture to the butter mixture a little at a time, beating just until incorporated. Refrigerate the dough for at least 2 hours and up to 2 weeks.
3. Preheat the oven to 350°F.
4. Scoop ice-cream-scoopfuls of dough onto ungreased baking sheets, spacing them about 1 inch apart. Bake until very well done and dark brown, about 30 minutes for crisp cookies. (Due to the molasses, these cookies get dark fairly quickly, and it can be difficult to tell if they are done enough.) Transfer to wire racks to cool. If they are still soft when they have cooled, flip them over and bake for 5 minutes more. (For softer cookies, bake for 12 to 15 minutes.)
5. When the cookies are cooled and crisp, use for ice cream sandwiches or roughly chop for folding into the ice cream. Store whole cookies in airtight containers at room temperature for up to 1 week.

Source: Godby, Jake; Vahey, Sean (2012-04-13). Humphrey Slocombe Ice Cream Book (Kindle Locations 2337-2349). Chronicle Books LLC. Kindle Edition.