Gluten Free Speculoos

One of my favourite cookies from my youth is the spicy crispy speculoos cookies we would get in the "imported foods" aisle of the grocery store.
After a lot of trial and error, we have perfected a gluten free version. This is NOT a recipe you can complete in an hour. Waiting times are important after mixing and after baking in order to develop the full flavour and texture of this amazing cookie.
"Five stars! Tastes like a traditional speculoos! cinnamon, spicy and crisp," says Will.
Makes 2 trays of small cookies.  

1 1/3 cup almond flour
2 Tbsp light buckwheat flour
2 Tbsp millet flour
2 Tbsp corn starch
1/2 tsp salt
1/2 tsp baking soda
1/2 tsp xanthan gum
3 tsp cinnamon
1/2 tsp ginger
1/4 tsp cardamom
1/4 tsp white pepper
1/8 tsp ground cloves

100 g butter (scant 1/2 cup)
1/2 cup demerara sugar
1 Tbsp fancy molasses
1 egg yolk

our first try.... not sliced.

GARNISH:
1 egg white (lightly beaten with 1/2 tsp water)
sliced almonds (optional)

INSTRUCTIONS:
Mix dry ingredients: flours & spices in a medium bowl. Set aside.
Cream butter, sugar and molasses thoroughly. Add egg yolk and mix until just mixed.
Add the flour mixture in two parts.
Form into a log, cover and refrigerate over night. DO NOT SKIP THIS STEP!
Preheat oven to 350F. Line two cookie trays with parchment paper or silicon sheet.
(Although you can just make small balls of dough and press, we found that slicing the chilled dough works best.) 
Cut the log into thin slices, approximately 3/16" thick. Lay on the lined cookie sheets. Press each cookie (use a little bit of parchment paper to keep the press from sticking). You can use a traditional wooden cookie press, potato masher or like we did, a gnocchi press. Should be about 1/8th inch thick when you are done.
It's important that they are the same thickness so they cook evenly. Timing is critical.
Brush with egg white beaten with 1/2 tsp water. Press almond slices into the top of each cookie if you like.
Bake in the middle of the oven at 350F for 12 minutes.
Remove from oven. As soon as you are able to move them without breaking, transfer each cookie carefully to cooling rack. Let them cool completely to develop the full crisp.
So worth the wait!