Preheat the oven to 350°F. Line two large baking sheets with unbleached parchment paper. Cut two additional pieces of parchment paper for rolling out the dough.
In a large mixing bowl, combine the melted butter, maple sugar, and egg. Stir until creamy. Add the maple syrup and vanilla. Stir to combine.
Add the NADA flour, baking soda, and sea salt. Stir until a smooth dough forms. It should be soft and easy to work with your hands. If the dough seems too sticky, knead in a little more flour until the dough is smooth and soft.
Lightly dust one piece of parchment paper with some NADA flour and place the dough ball on the parchment paper. Flatten the ball slightly with your palm, then place the other piece of parchment paper on top and use a rolling pin to roll out the dough.
For thin and crunchy animal crackers, roll out the dough until it is just over ⅛ inch thick. For soft animal crackers, don't roll the dough out any thinner than ¼ inch thick.
Use animal cracker cookie cutters to cut out shapes from the dough. Transfer the animal cookies to the baking trays using a spatula if necessary. You can place the crackers fairly close together since they won't puff or spread very much.
Bake for 10-15 minutes. The animal crackers should be just starting to brown on the bottoms. Allow the animal crackers to cool completely on a cooling rack before frosting or storing.
Notes
*You can use 1 cup + 1/4 cup of cassava flour in place of NADA flour.