In a large bowl, whisk together gluten-free flour, baking soda, and baking powder.
Place sugar and butter in the bowl of an electric mixer with a paddle attachment. Cream until smooth.
Add spices and salt to creamed sugar in the electric mixer. Mix on low until combined.
Beat the eggs and molasses into the creamed sugar mixture.
Add flour mixture and mix on low speed until everything is combined.
Divide dough in half and place each half on a piece of plastic wrap. Pat the dough into flat disks, wrap completely, and chill in the refrigerator for 2 hours or overnight.
Preheat oven to 350 degrees (325 degrees on convection setting).
On a Silpap mat, roll dough between 2 pieces of parchment paper. Using 1/4" thick dough rolling guides will ensure even thickness of cookies. Place on a baking tray and put in the freezer for 15 minutes to chill. Repeat with the other half of the dough.
Remove dough from the freezer. Peel off the top sheet of parchment paper to loosen from dough. Replace the top sheet of parchment paper; gently flip over; peel off the current top sheet of parchment paper. Cut cookie shapes with your favorite cookie cutters. Place on a cookie sheet lined with parchment paper. Do not overcrowd to prevent cookies from spreading during baking.
Bake for 10-12 minutes (6-8 minutes on convection setting), rotating halfway through baking time. Cool on cookie sheets. Decorate with royal icing when cool to the touch.